Thursday, December 28, 2023

Re: [electricboats] Recommendation for 48 v inboard motor + generator.

I couldn’t get comfortable with the idea of re-fueling with a funnel either. I ended up getting a new 3.8KW dual fuel electric start generator from Firman for a little over $700. I have it strapped down in a segregated seat locker with the exhaust plumbed to an un-used espar heater exhaust. Also added two 110 cfm quiet equipment fans the evacuate the heat. Initial tests this fall went well and I have adjusted the charger amps to optimize the draw on the generator. I have also found it’s a little quieter on propane. This spring I plan to figure out my zero loss cruise speed. 
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Tuesday, December 26, 2023

Re: [electricboats] Recommendation for 48 v inboard motor + generator.

I have that exact Westinghouse generator at home to save my ice cream when the power goes out.  Decent unit.   Access to the carb for cleaning could be better?  I had to disassemble it to clean it out after the unit sat un-used with gas left in it and the carb became fouled.  Easy enough fix once I got to the carb.  Would be better if the gas cutoff didn't also shut off the motor so you could run the carb dry.  

I had intended to try it on the boat to see how fast I could motor with it running through the charger and at zero draw from the batteries but I never got around to it.  I plan to do it after spring launch.  Maybe I'll have some data by the end of May.   It can supply more power than I can use through my 1500W charger. 

Another thing to consider is motor sailing. It greatly extends range.   I do have some data on that from last summer.    Should be quite relevant to you with same boat though the prop match is a very important factor.  

Motor Sailing Data Point Sunday September 17, 2023
Pearson 10M, 12,500 lbs, 18" 3 blade prop, 3:1 reduction, full main and 100% headsail
Wind S 5-8 diminishing to 0-2, shifting to N 0-2, building to 7-10, Waves <2
TWA 126, TWS 7.1, BSP 5.2, Watts 1024, RPM 1238 (prop RPM 412)
Estimated range 70 miles at this rate and conditions. 

What is your AC charging setup? 

Sodus to Sackets is 55 nmi.  Seems like a manageable single day to me.  I would never expect to motor the whole way.   I would head out a couple hours before dawn and expect to average 5 knots.  In a couple hrs before sunset.  Any wind direction but NE which would make it a beat.  A good small craft advisory with west wind would make a quick trip of it with perhaps enough boat speed to do regen.  In fact I would probably wait for a day when it was blowing 20 to 25 from the NW if I could.  But that's just me.  I seek out those conditions and I am properly rigged to handle them.  


Dan Pfeifffer



On 2023-12-26 10:25 pm, Scott E Erdman via groups.io wrote:

Hi Dan,

Thanks very much for replying and once again thanks for your 10M page – a superb reference that I'm using all the time now!

So it looks like I have a decent line on a Westinghouse iGEN2500 which is 2,200 W output for $600. https://westinghouse.com/products/igen2500-inverter-generator

 

I do need to get a generator in the next few months because, though I don't want to be using it much, my boat will come out of storage in April or early May and the marina it is presently at will only give me about 2 weeks of slip time since they are full and I won't be there for the summer. I did find a marina in Saket's Harbor and it is about a 2-3 day trip from Sodus Bay to Saket's Harbor. Due to these considerations and unpredictability of the weather and crew availability around then, I plan to go via Oswego where there is a town dock with overnight slips that have power and I can recharge fully there as needed. Still I want to have backup onboard even though we will sail as much as possible and the trip is a favorable one for travel by sail.

 

I don't plan to use this very much but want to have it at the ready just in case I get stuck really needing it.

Down the road there will be a few passages where it will be needed – St. Lawrence Seaway, Detroit River – for all these I am hoping that it may be possible to split the trip in half, thirds or quarters for the power intensive section and just plan to recharge whenever possible. One of the folks at the marina my boat is at went on and on and on about the Georgian Islands – looks super for when I am retired in a few years and have the time to get my boat up there and back in a season or so –

 

I am sure I'll have some more questions about the 10M. I have to reconnect the water system in mine so that is my main item aside from fixing the anchor light. Very much looking forward to spring!

 

Thanks again,

Scott

 

 

 

From: electricboats@groups.io <electricboats@groups.io> On Behalf Of Dan Pfeiffer
Sent: Tuesday, December 26, 2023 9:37 PM
To: electricboats@groups.io
Subject: Re: [electricboats] Recommendation for 48 v inboard motor + generator.

 

The answer to your question is (of course), it depends.    What is the output capacity of your AC charging system?  The gas generators you are considering are 120VAC output?  (The 5,000 watt may have a 220VAC output?)  You will be delivering the power to the batteries or the motor through the battery charger that you would plug in to shore power.  That means you have a max power limit that is set by the charger output.  If your charger output is 1500 watts max that's your limit.  You can't get more through the charger.  So you can't use any generator capacity beyond what the charger can put through to the battteries/motor.  

You have  speed limit on generator of whatever the max output of the charger is.  If it's 1500 watts that's all you can deliver from the genset through the charger regardless of the genset output capacity.  For your boat (assuming a well matched prop) that going to be about 4 knots.  Probably a bit less but I don't know the details of the installation (reduction, prop specs).   You can go faster but you'll be drawing the additional required power from the batteries. 

You can increase the charger capacity but there is no point in having a generator that has capacity several times what you can actually use?  My charger (Thunderstruck EV TSM2500) puts out 1500 watts with 120VAC input.  If I had 220VAC it could put out 2500 watts.  So a 220 VAC generator of 2500 watts could in theory get me motoring at about 5kts.  These chargers can be paralleled and two of them would get me to 5000 watts and 6kts continuous with a 220VAC generator. 

But there are some other limits as you start to try to motor at higher speeds.  Mainly heat.  Can your motor run at that output level continuously?  That's why I went with the 12kW liquid cooled motor.  It can.  The 10kW?  Not sure what it's limits are but its quite a bit lower for continuous operation. 

My project (same boat) is still developing and I thought I would want about 10kW of generator capacity to get continuous motoring speeds of 6+ knots (need that to transit Detroit river in reasonable time) but after running the electric drive for a few seasons I think I would be fine with 5 or 6kW.

As to the generator, I would rather NOT have a gas powered generator on board.  Refueling underway from a gas can sounds like a sloppy process.  Gas fumes can accumulate in the bilge though that can be mitigated with careful handling.   I would consider a propane powered unit.  Same fume issues but swapping out a new propane tank seems a lot easier at sea than re-filling the gas tank on the generator.  A little less output on propane Vs gas but the handling advantages seem worth it to me.  And these generators are strictly for above deck use.  Same for the fuel storage. 


Dan Pfeiffer


More on limits here:
http://dan.pfeiffer.net/10m/electric_drive_limits.htm

More on gensets:
http://dan.pfeiffer.net/10m/diesel_genset.htm





On 2023-12-26 1:46 pm, Scott E Erdman via groups.io wrote:

Hey Folks - I apologize for not maybe having all the specifics needed for this but related to this thread and a somewhat more simple question:

I did buy the Pearson 10M that had been converted to 10 kW Thunderstruck with 2x24 x 2 48V bank w/ 196 AH. 
Presently there is no other way on the boat to recharge other than plugged in on a slip. 
Looking at everything, I figure that purchasing a gas generator is the best insurance on expanding range and dealing with extended draw conditions (currents, etc)
So my question is this - does it make a big difference whether the generator I get is 2,000 vs. 5000 W ? 
I am looking on Craigslist and I can find quite a few used 5,000 W generators for good prices - I expect space is a consideration as well. I guess my main question is what would I gain from getting a 5,000 W generator vs. the smaller, more portable and perhaps more quiet 2,000W ones?

Trying to take care of some of these purchases this winter -

Thanks,

 

Re: [electricboats] Recommendation for 48 v inboard motor + generator.

Scott, the thing you MUST keep in mind about small gasoline generators is that you ABSOLUTELY MUST run them at least every 2 weeks.  If you do that, they will start and run great.  If you leave it sitting for a month or two, you may well be disappointed the next time you try to start it.   You don't have to use it, just start it and let it run for 10-15 min.

Good luck!
John

On Tuesday, December 26, 2023 at 09:25:31 PM CST, Scott E Erdman via groups.io <seerdman=syr.edu@groups.io> wrote:


Hi Dan,

Thanks very much for replying and once again thanks for your 10M page – a superb reference that I'm using all the time now!

So it looks like I have a decent line on a Westinghouse iGEN2500 which is 2,200 W output for $600. https://westinghouse.com/products/igen2500-inverter-generator

 

I do need to get a generator in the next few months because, though I don't want to be using it much, my boat will come out of storage in April or early May and the marina it is presently at will only give me about 2 weeks of slip time since they are full and I won't be there for the summer. I did find a marina in Saket's Harbor and it is about a 2-3 day trip from Sodus Bay to Saket's Harbor. Due to these considerations and unpredictability of the weather and crew availability around then, I plan to go via Oswego where there is a town dock with overnight slips that have power and I can recharge fully there as needed. Still I want to have backup onboard even though we will sail as much as possible and the trip is a favorable one for travel by sail.

 

I don't plan to use this very much but want to have it at the ready just in case I get stuck really needing it.

Down the road there will be a few passages where it will be needed – St. Lawrence Seaway, Detroit River – for all these I am hoping that it may be possible to split the trip in half, thirds or quarters for the power intensive section and just plan to recharge whenever possible. One of the folks at the marina my boat is at went on and on and on about the Georgian Islands – looks super for when I am retired in a few years and have the time to get my boat up there and back in a season or so –

 

I am sure I'll have some more questions about the 10M. I have to reconnect the water system in mine so that is my main item aside from fixing the anchor light. Very much looking forward to spring!

 

Thanks again,

Scott

 

 

From: electricboats@groups.io <electricboats@groups.io> On Behalf Of Dan Pfeiffer
Sent: Tuesday, December 26, 2023 9:37 PM
To: electricboats@groups.io
Subject: Re: [electricboats] Recommendation for 48 v inboard motor + generator.

 

The answer to your question is (of course), it depends.    What is the output capacity of your AC charging system?  The gas generators you are considering are 120VAC output?  (The 5,000 watt may have a 220VAC output?)  You will be delivering the power to the batteries or the motor through the battery charger that you would plug in to shore power.  That means you have a max power limit that is set by the charger output.  If your charger output is 1500 watts max that's your limit.  You can't get more through the charger.  So you can't use any generator capacity beyond what the charger can put through to the battteries/motor.  

You have  speed limit on generator of whatever the max output of the charger is.  If it's 1500 watts that's all you can deliver from the genset through the charger regardless of the genset output capacity.  For your boat (assuming a well matched prop) that going to be about 4 knots.  Probably a bit less but I don't know the details of the installation (reduction, prop specs).   You can go faster but you'll be drawing the additional required power from the batteries. 

You can increase the charger capacity but there is no point in having a generator that has capacity several times what you can actually use?  My charger (Thunderstruck EV TSM2500) puts out 1500 watts with 120VAC input.  If I had 220VAC it could put out 2500 watts.  So a 220 VAC generator of 2500 watts could in theory get me motoring at about 5kts.  These chargers can be paralleled and two of them would get me to 5000 watts and 6kts continuous with a 220VAC generator. 

But there are some other limits as you start to try to motor at higher speeds.  Mainly heat.  Can your motor run at that output level continuously?  That's why I went with the 12kW liquid cooled motor.  It can.  The 10kW?  Not sure what it's limits are but its quite a bit lower for continuous operation. 

My project (same boat) is still developing and I thought I would want about 10kW of generator capacity to get continuous motoring speeds of 6+ knots (need that to transit Detroit river in reasonable time) but after running the electric drive for a few seasons I think I would be fine with 5 or 6kW.

As to the generator, I would rather NOT have a gas powered generator on board.  Refueling underway from a gas can sounds like a sloppy process.  Gas fumes can accumulate in the bilge though that can be mitigated with careful handling.   I would consider a propane powered unit.  Same fume issues but swapping out a new propane tank seems a lot easier at sea than re-filling the gas tank on the generator.  A little less output on propane Vs gas but the handling advantages seem worth it to me.  And these generators are strictly for above deck use.  Same for the fuel storage. 


Dan Pfeiffer


More on limits here:
http://dan.pfeiffer.net/10m/electric_drive_limits.htm

More on gensets:
http://dan.pfeiffer.net/10m/diesel_genset.htm





On 2023-12-26 1:46 pm, Scott E Erdman via groups.io wrote:

Hey Folks - I apologize for not maybe having all the specifics needed for this but related to this thread and a somewhat more simple question:

I did buy the Pearson 10M that had been converted to 10 kW Thunderstruck with 2x24 x 2 48V bank w/ 196 AH. 
Presently there is no other way on the boat to recharge other than plugged in on a slip. 
Looking at everything, I figure that purchasing a gas generator is the best insurance on expanding range and dealing with extended draw conditions (currents, etc)
So my question is this - does it make a big difference whether the generator I get is 2,000 vs. 5000 W ? 
I am looking on Craigslist and I can find quite a few used 5,000 W generators for good prices - I expect space is a consideration as well. I guess my main question is what would I gain from getting a 5,000 W generator vs. the smaller, more portable and perhaps more quiet 2,000W ones?

Trying to take care of some of these purchases this winter -

Thanks,

Re: [electricboats] Recommendation for 48 v inboard motor + generator.

Hi Dan,

Thanks very much for replying and once again thanks for your 10M page – a superb reference that I'm using all the time now!

So it looks like I have a decent line on a Westinghouse iGEN2500 which is 2,200 W output for $600. https://westinghouse.com/products/igen2500-inverter-generator

 

I do need to get a generator in the next few months because, though I don't want to be using it much, my boat will come out of storage in April or early May and the marina it is presently at will only give me about 2 weeks of slip time since they are full and I won't be there for the summer. I did find a marina in Saket's Harbor and it is about a 2-3 day trip from Sodus Bay to Saket's Harbor. Due to these considerations and unpredictability of the weather and crew availability around then, I plan to go via Oswego where there is a town dock with overnight slips that have power and I can recharge fully there as needed. Still I want to have backup onboard even though we will sail as much as possible and the trip is a favorable one for travel by sail.

 

I don't plan to use this very much but want to have it at the ready just in case I get stuck really needing it.

Down the road there will be a few passages where it will be needed – St. Lawrence Seaway, Detroit River – for all these I am hoping that it may be possible to split the trip in half, thirds or quarters for the power intensive section and just plan to recharge whenever possible. One of the folks at the marina my boat is at went on and on and on about the Georgian Islands – looks super for when I am retired in a few years and have the time to get my boat up there and back in a season or so –

 

I am sure I'll have some more questions about the 10M. I have to reconnect the water system in mine so that is my main item aside from fixing the anchor light. Very much looking forward to spring!

 

Thanks again,

Scott

 

 

From: electricboats@groups.io <electricboats@groups.io> On Behalf Of Dan Pfeiffer
Sent: Tuesday, December 26, 2023 9:37 PM
To: electricboats@groups.io
Subject: Re: [electricboats] Recommendation for 48 v inboard motor + generator.

 

The answer to your question is (of course), it depends.    What is the output capacity of your AC charging system?  The gas generators you are considering are 120VAC output?  (The 5,000 watt may have a 220VAC output?)  You will be delivering the power to the batteries or the motor through the battery charger that you would plug in to shore power.  That means you have a max power limit that is set by the charger output.  If your charger output is 1500 watts max that's your limit.  You can't get more through the charger.  So you can't use any generator capacity beyond what the charger can put through to the battteries/motor.  

You have  speed limit on generator of whatever the max output of the charger is.  If it's 1500 watts that's all you can deliver from the genset through the charger regardless of the genset output capacity.  For your boat (assuming a well matched prop) that going to be about 4 knots.  Probably a bit less but I don't know the details of the installation (reduction, prop specs).   You can go faster but you'll be drawing the additional required power from the batteries. 

You can increase the charger capacity but there is no point in having a generator that has capacity several times what you can actually use?  My charger (Thunderstruck EV TSM2500) puts out 1500 watts with 120VAC input.  If I had 220VAC it could put out 2500 watts.  So a 220 VAC generator of 2500 watts could in theory get me motoring at about 5kts.  These chargers can be paralleled and two of them would get me to 5000 watts and 6kts continuous with a 220VAC generator. 

But there are some other limits as you start to try to motor at higher speeds.  Mainly heat.  Can your motor run at that output level continuously?  That's why I went with the 12kW liquid cooled motor.  It can.  The 10kW?  Not sure what it's limits are but its quite a bit lower for continuous operation. 

My project (same boat) is still developing and I thought I would want about 10kW of generator capacity to get continuous motoring speeds of 6+ knots (need that to transit Detroit river in reasonable time) but after running the electric drive for a few seasons I think I would be fine with 5 or 6kW.

As to the generator, I would rather NOT have a gas powered generator on board.  Refueling underway from a gas can sounds like a sloppy process.  Gas fumes can accumulate in the bilge though that can be mitigated with careful handling.   I would consider a propane powered unit.  Same fume issues but swapping out a new propane tank seems a lot easier at sea than re-filling the gas tank on the generator.  A little less output on propane Vs gas but the handling advantages seem worth it to me.  And these generators are strictly for above deck use.  Same for the fuel storage. 


Dan Pfeiffer


More on limits here:
http://dan.pfeiffer.net/10m/electric_drive_limits.htm

More on gensets:
http://dan.pfeiffer.net/10m/diesel_genset.htm





On 2023-12-26 1:46 pm, Scott E Erdman via groups.io wrote:

Hey Folks - I apologize for not maybe having all the specifics needed for this but related to this thread and a somewhat more simple question:

I did buy the Pearson 10M that had been converted to 10 kW Thunderstruck with 2x24 x 2 48V bank w/ 196 AH. 
Presently there is no other way on the boat to recharge other than plugged in on a slip. 
Looking at everything, I figure that purchasing a gas generator is the best insurance on expanding range and dealing with extended draw conditions (currents, etc)
So my question is this - does it make a big difference whether the generator I get is 2,000 vs. 5000 W ? 
I am looking on Craigslist and I can find quite a few used 5,000 W generators for good prices - I expect space is a consideration as well. I guess my main question is what would I gain from getting a 5,000 W generator vs. the smaller, more portable and perhaps more quiet 2,000W ones?

Trying to take care of some of these purchases this winter -

Thanks,

Re: [electricboats] Recommendation for 48 v inboard motor + generator.

The answer to your question is (of course), it depends.    What is the output capacity of your AC charging system?  The gas generators you are considering are 120VAC output?  (The 5,000 watt may have a 220VAC output?)  You will be delivering the power to the batteries or the motor through the battery charger that you would plug in to shore power.  That means you have a max power limit that is set by the charger output.  If your charger output is 1500 watts max that's your limit.  You can't get more through the charger.  So you can't use any generator capacity beyond what the charger can put through to the battteries/motor.  

You have  speed limit on generator of whatever the max output of the charger is.  If it's 1500 watts that's all you can deliver from the genset through the charger regardless of the genset output capacity.  For your boat (assuming a well matched prop) that going to be about 4 knots.  Probably a bit less but I don't know the details of the installation (reduction, prop specs).   You can go faster but you'll be drawing the additional required power from the batteries. 

You can increase the charger capacity but there is no point in having a generator that has capacity several times what you can actually use?  My charger (Thunderstruck EV TSM2500) puts out 1500 watts with 120VAC input.  If I had 220VAC it could put out 2500 watts.  So a 220 VAC generator of 2500 watts could in theory get me motoring at about 5kts.  These chargers can be paralleled and two of them would get me to 5000 watts and 6kts continuous with a 220VAC generator. 

But there are some other limits as you start to try to motor at higher speeds.  Mainly heat.  Can your motor run at that output level continuously?  That's why I went with the 12kW liquid cooled motor.  It can.  The 10kW?  Not sure what it's limits are but its quite a bit lower for continuous operation. 

My project (same boat) is still developing and I thought I would want about 10kW of generator capacity to get continuous motoring speeds of 6+ knots (need that to transit Detroit river in reasonable time) but after running the electric drive for a few seasons I think I would be fine with 5 or 6kW.

As to the generator, I would rather NOT have a gas powered generator on board.  Refueling underway from a gas can sounds like a sloppy process.  Gas fumes can accumulate in the bilge though that can be mitigated with careful handling.   I would consider a propane powered unit.  Same fume issues but swapping out a new propane tank seems a lot easier at sea than re-filling the gas tank on the generator.  A little less output on propane Vs gas but the handling advantages seem worth it to me.  And these generators are strictly for above deck use.  Same for the fuel storage. 


Dan Pfeiffer


More on limits here:
http://dan.pfeiffer.net/10m/electric_drive_limits.htm

More on gensets:
http://dan.pfeiffer.net/10m/diesel_genset.htm




On 2023-12-26 1:46 pm, Scott E Erdman via groups.io wrote:

Hey Folks - I apologize for not maybe having all the specifics needed for this but related to this thread and a somewhat more simple question:

I did buy the Pearson 10M that had been converted to 10 kW Thunderstruck with 2x24 x 2 48V bank w/ 196 AH. 
Presently there is no other way on the boat to recharge other than plugged in on a slip. 
Looking at everything, I figure that purchasing a gas generator is the best insurance on expanding range and dealing with extended draw conditions (currents, etc)
So my question is this - does it make a big difference whether the generator I get is 2,000 vs. 5000 W ? 
I am looking on Craigslist and I can find quite a few used 5,000 W generators for good prices - I expect space is a consideration as well. I guess my main question is what would I gain from getting a 5,000 W generator vs. the smaller, more portable and perhaps more quiet 2,000W ones?

Trying to take care of some of these purchases this winter -

Thanks,

Re: [electricboats] Recommendation for 48 v inboard motor + generator.

If you’re thinking a portable gas generator, I like the Harbor Freight 3.5kW inverter unit. Quiet. Electric start. Wait for a 25% off coupon.  

 

https://www.harborfreight.com/generators-engines/generators/3500-watt-super-quiet-inverter-generator-with-co-secure-technology-59137.html


I am just now putting together a 48v charger to maximize the available current (3.0kW) of the generator. I’m using a pair of 24v chargers in series. 

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Re: [electricboats] Recommendation for 48 v inboard motor + generator.

Hey Folks - I apologize for not maybe having all the specifics needed for this but related to this thread and a somewhat more simple question:

I did buy the Pearson 10M that had been converted to 10 kW Thunderstruck with 2x24 x 2 48V bank w/ 196 AH. 
Presently there is no other way on the boat to recharge other than plugged in on a slip. 
Looking at everything, I figure that purchasing a gas generator is the best insurance on expanding range and dealing with extended draw conditions (currents, etc)
So my question is this - does it make a big difference whether the generator I get is 2,000 vs. 5000 W ? 
I am looking on Craigslist and I can find quite a few used 5,000 W generators for good prices - I expect space is a consideration as well. I guess my main question is what would I gain from getting a 5,000 W generator vs. the smaller, more portable and perhaps more quiet 2,000W ones?

Trying to take care of some of these purchases this winter -

Thanks,
_._,_._,_

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Friday, December 1, 2023

Re: [electricboats] Parallel LiFePO4 Packs

Great advice.

My 30kwh pack batteries (lithium ion, 20P(1.5kwh, 42vnom)) are only connected to a charging system after reaching somewhere between 33 and 36v, and then only charging overnight to 48v (max. batt spec is 49.1v).  I manually disconnect the next day.  Going further, I do not totally trust BMS cards (and for good reason) and so I only power them up maybe once every 6-18months to check cell balance across the 240 cell pairs.  Even with that, I have heard from at least one European owner of THINK cars with these batteries/BMS indicate to me that he has seen even unpowered BMS cards drain a cell pair.  So there's that risk also.  Further on the non-trusting side, the software I wrote to communicate with 20 BMS cards and manage all the balancing only enables balancing on one of the 20 module strings at a time---only the worst one.  This has the advantages of minimizing the number of bypass circuits that are enabled and lowering the risk that they will degrade quicker or worse, that one of them might get stuck ON.  Since all the modules are in parallel, as a string is bypass balancing, the other parallel strings will supply that string with current, maintaining the string voltage and only slowly dropping the pack voltage---far better than bypassing ALL the high cells in the pack to bring them all down to the low voltage.  Works like a charm.

 

Anyway, stay safe.

 

-MT

 

From: electricboats@groups.io [mailto:electricboats@groups.io] On Behalf Of Harley Clark
Sent: Wednesday, November 22, 2023 5:22 PM
To: electricboats@groups.io
Subject: Re: [electricboats] Parallel LiFePO4 Packs

 

I don't know if it is general knowledge that fully charged LFPO batteries must be disconnected from a charging source.  Lately I have heard of some unexplained fires in boats that are docked while their owners are absent and have wondered if the batteries were being over charged by solar panels or wind. The BMS should be set up to physically disconnect the batteries. 

This can be complicated by solar and wind if these sources must be redirected to another load path to consume this unwanted charging current.

Hopefully, Everyone is hearing old news

 

On Tue, Nov 21, 2023 at 10:07 AM THOMAS VANDERMEULEN <tvinypsi@gmail.com> wrote:

wow, Reuben ... !  A full MegaWatt hours of capacity?!?!   According to one source, that's enough to power the average household of 5-weeks!!
What is your cruising range on motor alone?  Must be close somewhere around 70 Nautical Miles.
[-tv]

Wednesday, November 22, 2023

Re: [electricboats] Parallel LiFePO4 Packs

I don't know if it is general knowledge that fully charged LFPO batteries must be disconnected from a charging source.  Lately I have heard of some unexplained fires in boats that are docked while their owners are absent and have wondered if the batteries were being over charged by solar panels or wind. The BMS should be set up to physically disconnect the batteries. 
This can be complicated by solar and wind if these sources must be redirected to another load path to consume this unwanted charging current.
Hopefully, Everyone is hearing old news

On Tue, Nov 21, 2023 at 10:07 AM THOMAS VANDERMEULEN <tvinypsi@gmail.com> wrote:
wow, Reuben ... !  A full MegaWatt hours of capacity?!?!   According to one source, that's enough to power the average household of 5-weeks!!
What is your cruising range on motor alone?  Must be close somewhere around 70 Nautical Miles.
[-tv]

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Tuesday, November 21, 2023

Re: [electricboats] Parallel LiFePO4 Packs

 



12m - over 20,000# - has 5kW solar - 2 each 10kW Motenergy water-cooled motors  

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Re: [electricboats] Parallel LiFePO4 Packs

My mistake, entirely, Reuben ... thanks ... but even at 50kWh, it's still a very substantial pack!!  Given a range of 25NM, then, I gather it's a very substantial boat as well.
Fair winds!
[-tv]
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Re: [electricboats] Parallel LiFePO4 Packs


That's what I have in my Tesla :)

On 11/21/23 12:28 PM, Reuben Trane via groups.io wrote:
Check your math? 1,000AH/48v is 50kWh. I get about 25NM at 5 knots. 


--   Jeff LaCoursiere  StratusTalk, Inc.  703 496 4990 x108  815 546 6599 cell

Re: [electricboats] Parallel LiFePO4 Packs

Check your math? 1,000AH/48v is 50kWh. I get about 25NM at 5 knots. 
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Re: [electricboats] Parallel LiFePO4 Packs

wow, Reuben ... !  A full MegaWatt hours of capacity?!?!   According to one source, that's enough to power the average household of 5-weeks!!
What is your cruising range on motor alone?  Must be close somewhere around 70 Nautical Miles.
[-tv]
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Re: [electricboats] Electric motor size for 48' cat

Hey Jack,

Thanks for that info!  That's a pretty close comparison, so that's very helpful.  More and more, I'm thinking the Thunderstruck 12k package at 48v seems like the right fit.
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Monday, November 20, 2023

Re: [electricboats] Parallel LiFePO4 Packs

Hi Chris, 
I know what you mean meaning having the flow through the BMS unit rather than it control a relay, but what turned me is that with the daly unit you can set limits to cut charging but still have discharging going, which i found to be a good fail safe / back up, rather than just drop the relay and the bank should something go amiss. I think my thought process for my set up tends to be wavered by my background in the O&G industry, we have back ups for back ups. hence i like the idea of the 48V 2 banks which can run together or individually for propulsion. We are also having a independent 12 volt bank for the rest of the boat as another back up :-)

good luck with getting it all sorted and let me know how it all goes

cheers
kel
   
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Re: [electricboats] Parallel LiFePO4 Packs

Hi mate
the daly BMS has 300, 400 and 500A version in the EV/Boat range, when you run 2 BMS's you then add a parallel module to each one.
my motors are twin 48V / 15kW , 1,000AH impressive :-)

cheers
kel
 
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Re: [electricboats] Parallel LiFePO4 Packs

I would avoid Daly. They have a nice website, tons of videos, ect. I consider most of it vaporware. It simply doesn't work as its supposed to or just doesn't work. If you have any chance of the cells balancing, you need to buy the cell balancer. 

On top of that, they just don't last long. Forums are littered with comments from people went through multiple Daly products before they gave up and bought something else. 

I don't think their parallel protector is needed or does anything. 

Check out JK BMS. 
 
Matt Foley 
Sunlight Conversions
Perpetual Energy, LLC
201-914-0466

ABYC Certified Marine 
Electrical Technician 


On Monday, November 20, 2023 at 12:32:01 PM EST, Kel Bryant <kelbryant@hotmail.com> wrote:


Hi Chris
I am building a 47ft cat with 2 x ME1616 motor, am going to install 2 x 16 string 304ah banks in parallel, mainly for a back up should we have a problem, we are going to use 2 x BMS's with active balancing and a parallel protector  Daly BMS have such an animal, which from my research  seems to fit the bill,  my 48 bank / banks will also charge on 12 volt house bank which is 300ah via a DC-DC charger and another BMS, 

cheers
kel


https://www.dalybms.com/daly-smart-bms-500a-with-bt-touching-display-for-low-speed-car-rv-boat-product/

Re: [electricboats] Parallel LiFePO4 Packs

Hi Kel,
Thanks for that. I did see the Daly Pack Parallel Module. I have not been able to get comfortable with the BMS units where the charge and discharge current is passed through and regulated by it. I've settled on 1 string of cells at 304 Ah for now. I bought a REC 2Q BMS that just controls a contactor to interrupt charging/discharging if parameters get out of bounds. I like this way because it's easy to bypass the contactor in a pinch. REC do have the ability to parallel strings. I think (not sure) it would be 2 BMS plus a master module. I finally just had to get off the fence and do something, so I took the easy way out and went with a single string.

Chris

Sent from myPhone

On Nov 20, 2023, at 16:41, Reuben Trane via groups.io <rjtrane=me.com@groups.io> wrote:



Does the Daly BMS allow for 200A current - I'm guessing your motors are 48v/10kW?

I have twins in my cat but a single 1,000AH/48v pack with Winston cells - 16s. Much simpler than two packs. 


what model Daly handles parallel connections safely  

 

Re: [electricboats] Parallel LiFePO4 Packs

Does the Daly BMS allow for 200A current - I’m guessing your motors are 48v/10kW?

I have twins in my cat but a single 1,000AH/48v pack with Winston cells - 16s. Much simpler than two packs. 


what model Daly handles parallel connections safely  

 

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Re: [electricboats] Motor recommendation

I’d think a 48v/10kW or 12kW is big enough. Check the kits at thunderstruck-EV. com. They may have good recommendations for your boat. I have a pair if 10kW Motenergy water cooled with Sevcon Gen4 controllers and the Thunderstruck motor mounts/reduction pulleys. My cat is 40’ and over 20,000#. 
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Thursday, November 9, 2023

[electricboats] Motor recommendation

I have a Sabre 28-2 with a 30 hp Atomic 4 engine.  What size electric motor should I consider?
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Re: [electricboats] Parallel LiFePO4 Packs

Hi Chris
I am building a 47ft cat with 2 x ME1616 motor, am going to install 2 x 16 string 304ah banks in parallel, mainly for a back up should we have a problem, we are going to use 2 x BMS's with active balancing and a parallel protector  Daly BMS have such an animal, which from my research  seems to fit the bill,  my 48 bank / banks will also charge on 12 volt house bank which is 300ah via a DC-DC charger and another BMS, 

cheers
kel


https://www.dalybms.com/daly-smart-bms-500a-with-bt-touching-display-for-low-speed-car-rv-boat-product/
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Re: [electricboats] Parallel LiFePO4 Packs

Stew,
Thanks for the input. Check out The Off Grid Garage on YouTube. This guy has done a lot of testing with parallel banks and parallel cells. His testing makes it look like it's no big deal. He's also very entertaining. 

Chris

Sent from myPhone

On Nov 9, 2023, at 11:16, Stew <stewart.reed@free.fr> wrote:

Interesting article - thanks for posting - needs a few reads to fully understand!
I have had 2 x 16s sets in parallel (2 x 16 272Ah lifepo4 cells) set up with an Overkill 16s bms for each. I run them together but can switch out either bank if required. The bms allows monitoring of all cells.
The article has made me wonder whether I should rethink and set up as a single bank with cells paired but not sure to be honest. Probably will do more testing as is to see if any limitations.
Installed in a Jeanneau 36' GinFizz with ME1616 motor and Sevcon 6 controller.

Re: [electricboats] Parallel LiFePO4 Packs

Interesting article - thanks for posting - needs a few reads to fully understand!
I have had 2 x 16s sets in parallel (2 x 16 272Ah lifepo4 cells) set up with an Overkill 16s bms for each. I run them together but can switch out either bank if required. The bms allows monitoring of all cells.
The article has made me wonder whether I should rethink and set up as a single bank with cells paired but not sure to be honest. Probably will do more testing as is to see if any limitations.
Installed in a Jeanneau 36' GinFizz with ME1616 motor and Sevcon 6 controller.
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Re: [electricboats] sevcon controlled electric drive does not rotate

The motor itself is not sealed well enough, and in this saildrive orgintion water can collect on the top of the motor and seep in .
The 4 screws that hold the encoder down can also short out the board, it helps to put fiber washers under these . Sometimes just removing the screws fixes the encoder problem.

Brian D. HAll





ThunderStruck Motors, LLC
2985 Dutton Ave. Ste 3
Santa Rosa, CA 95407
Tel: (707) 578-7973
Fax: (707) 581-1860
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[electricboats] San Juan 24


Anybody interested in a San Juan 24 in the seattle area?
Cheap
Needs a motor

Cheers

Re: [electricboats] Parallel LiFePO4 Packs

Thanks guys. I've been watching some YouTube videos from the Off Grid Garage. The guy is doing parallel 48 volt strings. I'm warming back up to the idea of doing just this. Need to do some more research, but this seems possible and safe.

Chris 

Sent from myPhone

On Nov 8, 2023, at 21:05, Myles Twete <matwete@comcast.net> wrote:



Or you can go with 2 strings, 2 BMS and combine the strings like you originally talked about.  But you don't have to make these formally "switchable" strings---they can be segregated for emergency or other reasons (e.g. separate charging) very easily with appropriate connector choices.  Fuses are always a good idea.

My pack is effectively composed of 20 separate nom. 42v strings all combined in parallel thru 20amp fuses.

That would ordinarily be a very expensive and complicated way to go (especially given also the 20 remote BMS cards I use) but the strings are comprised of modules including BMS cards that are ex-EV and relatively inexpensive.

So not counting cabling and fuses, one can pick up modules like this (including BMS cards) for $50/kwh or even less if you cut out the retailer.  I paid about this for the latest modules I picked up and could have gotten them for about half that.

So in my case, if I suddenly had a shorted cell (internal or external short), that string's fuse would blow and it would be some time before I'd discover it---eventually I'd discover it, but in the meantime that string would be isolated.  In several years of use (lithium ion) I have yet to see a shorted cell pair, though I do know there are several weaker or leaky cell pairs out of the 240 cell pairs in the pack.  Also, I can quickly isolate any or many strings by simply slipping off any particular "Radsok" connectors at the top of each stack.  The Radsok connectors also makes it quick and easy to remove one of the modules.

 

If these USED batteries were not available cheap, I'd probably still be running with flooded PbA or would have gone with a single- or dual-string LiFePo large-capacity pack as you are planning.

 

-MT

 

 

 

 

From: electricboats@groups.io [mailto:electricboats@groups.io] On Behalf Of ChristopherH via groups.io
Sent: Wednesday, November 8, 2023 2:26 PM
To: electricboats@groups.io
Subject: Re: [electricboats] Parallel LiFePO4 Packs

 

I found this great article by Orion BMS that discusses parallel strings. Reading this really makes me lean toward parallel cells as you wise gents previously suggested.

 

Thanks again for all the valuable input.

 

Chris 

 

Sent from myPhone



On Nov 8, 2023, at 16:58, ChristopherH via groups.io <clh5_98=yahoo.com@groups.io> wrote:



Reuben,

From what I've seen, Victron only have BMS for their line of packaged batteries in the 12 and 24 volt ranges.

 

Chris 

 

Sent from myPhone



On Nov 8, 2023, at 16:55, Chris Hudson <clh5_98@yahoo.com> wrote:

John,

Thanks for your input and good point about having an ace in the hole!

Chris 

 

Sent from myPhone



On Nov 8, 2023, at 16:22, john via groups.io <oak_box=yahoo.com@groups.io> wrote:



I don't have a LOT of experience with this, but am now running my electric dinghy with two separate 48V ebike batteries.

 

I like keeping them separate so that if one gets accidentally discharged (or any other failure), I still have a second battery to get home on.

 

On Wednesday, November 8, 2023 at 01:59:35 PM CST, Myles Twete <matwete@comcast.net> wrote:

 

 

Thought: Dangerous for the switch unless it's a break-before-make or other exclusive-or arrangement.

 

Why: You've been running for hours on one string, then decide to switch to the other.  If you thought that you'd just use a standard marine battery combiner switch, you could accidentally switch to "ALL" position, which would then put both strings in parallel thru the switch, quickly shorting it and possibly melting the housing.  Might also have a problem with that type of switch switching between each string.

 

With Lithium-Ion there's something to be said for having separate strings---ability to switch and get a higher pack voltage again for a time giving higher power/speed than if the strings were paralleled and slowly going down together.  But really, a slowly dropping voltage is better than one that drops much faster due to not paralleling.  Not as much of a big deal with LiFePo, but still, I'd tend to think paralleling is better.

 

Just a thought.

-MT

 

From: electricboats@groups.io [mailto:electricboats@groups.io] On Behalf Of ChristopherH via groups.io
Sent: Wednesday, November 8, 2023 11:49 AM
To: electricboats@groups.io
Subject: Re: [electricboats] Parallel LiFePO4 Packs

 

Bobkart,

Thanks for the reply. Actually I'm proposing to have 2 independent 16 cell strings with the ability to parallel them at the 48V level with switches, not at the cell level. Thoughts on that?

 

Chris 

Sent from myPhone

 

On Nov 8, 2023, at 14:40, bobkart <couch45@msn.com> wrote:



Connecting two 230Ah cells together in parallel (sixteen times) would allow you to treat the 32 cells as one large 16S 48V x 460Ah battery

BMS, load, charger, capacity monitoring would be none-the-wiser.

 

One concern of that configuration that wouldn't otherwise come up is if one cell in a two-cell pair were to fail.

If the failure is a short, it would bring the other cell with it.

 


From: electricboats@groups.io <electricboats@groups.io> on behalf of ChristopherH via groups.io <clh5_98=yahoo.com@groups.io>

Sent: Wednesday, November 8, 2023 10:34 AM
To: electricboats@groups.io <electricboats@groups.io>
Subject: [electricboats] Parallel LiFePO4 Packs

 

Hi Group,
My Morgan Out Island 41 is ready for new batteries. I'm ready to embrace LiFePO4. When I originally converted to electric I built and glassed in 2 battery boxes to hold 2 banks of 8 (16 batteries) golf cart batteries. I always run with both banks in parallel, but have the ability to run on just 1 and this has worked well. Unfortunately this size battery box doesn't make efficient use of most individual LiFePO4 cells. I would however be able to use 32 X 230Ah EVE cells in 1 battery box, leaving the other box for some other purpose. My questions: I'd like to be able to run the 2 X 16S strings in parallel. Is this possible with LiFePO4? Is it safe to do this? Any precautions? Would I have 2 separate BMS units? How about capacity monitoring for the 2 banks in parallel? I have a Victron 48V/5KVA Victron Quattro charger inverter. 
Thanks in advance for any assistance/suggestions.

Regards,
Chris Hudson

Sent from myPhone



Wednesday, November 8, 2023

Re: [electricboats] Parallel LiFePO4 Packs

Or you can go with 2 strings, 2 BMS and combine the strings like you originally talked about.  But you don't have to make these formally "switchable" strings---they can be segregated for emergency or other reasons (e.g. separate charging) very easily with appropriate connector choices.  Fuses are always a good idea.

My pack is effectively composed of 20 separate nom. 42v strings all combined in parallel thru 20amp fuses.

That would ordinarily be a very expensive and complicated way to go (especially given also the 20 remote BMS cards I use) but the strings are comprised of modules including BMS cards that are ex-EV and relatively inexpensive.

So not counting cabling and fuses, one can pick up modules like this (including BMS cards) for $50/kwh or even less if you cut out the retailer.  I paid about this for the latest modules I picked up and could have gotten them for about half that.

So in my case, if I suddenly had a shorted cell (internal or external short), that string's fuse would blow and it would be some time before I'd discover it---eventually I'd discover it, but in the meantime that string would be isolated.  In several years of use (lithium ion) I have yet to see a shorted cell pair, though I do know there are several weaker or leaky cell pairs out of the 240 cell pairs in the pack.  Also, I can quickly isolate any or many strings by simply slipping off any particular "Radsok" connectors at the top of each stack.  The Radsok connectors also makes it quick and easy to remove one of the modules.

 

If these USED batteries were not available cheap, I'd probably still be running with flooded PbA or would have gone with a single- or dual-string LiFePo large-capacity pack as you are planning.

 

-MT

 

 

 

 

From: electricboats@groups.io [mailto:electricboats@groups.io] On Behalf Of ChristopherH via groups.io
Sent: Wednesday, November 8, 2023 2:26 PM
To: electricboats@groups.io
Subject: Re: [electricboats] Parallel LiFePO4 Packs

 

I found this great article by Orion BMS that discusses parallel strings. Reading this really makes me lean toward parallel cells as you wise gents previously suggested.

 

Thanks again for all the valuable input.

 

Chris 

 

Sent from myPhone



On Nov 8, 2023, at 16:58, ChristopherH via groups.io <clh5_98=yahoo.com@groups.io> wrote:



Reuben,

From what I've seen, Victron only have BMS for their line of packaged batteries in the 12 and 24 volt ranges.

 

Chris 

 

Sent from myPhone



On Nov 8, 2023, at 16:55, Chris Hudson <clh5_98@yahoo.com> wrote:

John,

Thanks for your input and good point about having an ace in the hole!

Chris 

 

Sent from myPhone



On Nov 8, 2023, at 16:22, john via groups.io <oak_box=yahoo.com@groups.io> wrote:



I don't have a LOT of experience with this, but am now running my electric dinghy with two separate 48V ebike batteries.

 

I like keeping them separate so that if one gets accidentally discharged (or any other failure), I still have a second battery to get home on.

 

On Wednesday, November 8, 2023 at 01:59:35 PM CST, Myles Twete <matwete@comcast.net> wrote:

 

 

Thought: Dangerous for the switch unless it's a break-before-make or other exclusive-or arrangement.

 

Why: You've been running for hours on one string, then decide to switch to the other.  If you thought that you'd just use a standard marine battery combiner switch, you could accidentally switch to "ALL" position, which would then put both strings in parallel thru the switch, quickly shorting it and possibly melting the housing.  Might also have a problem with that type of switch switching between each string.

 

With Lithium-Ion there's something to be said for having separate strings---ability to switch and get a higher pack voltage again for a time giving higher power/speed than if the strings were paralleled and slowly going down together.  But really, a slowly dropping voltage is better than one that drops much faster due to not paralleling.  Not as much of a big deal with LiFePo, but still, I'd tend to think paralleling is better.

 

Just a thought.

-MT

 

From: electricboats@groups.io [mailto:electricboats@groups.io] On Behalf Of ChristopherH via groups.io
Sent: Wednesday, November 8, 2023 11:49 AM
To: electricboats@groups.io
Subject: Re: [electricboats] Parallel LiFePO4 Packs

 

Bobkart,

Thanks for the reply. Actually I'm proposing to have 2 independent 16 cell strings with the ability to parallel them at the 48V level with switches, not at the cell level. Thoughts on that?

 

Chris 

Sent from myPhone

 

On Nov 8, 2023, at 14:40, bobkart <couch45@msn.com> wrote:



Connecting two 230Ah cells together in parallel (sixteen times) would allow you to treat the 32 cells as one large 16S 48V x 460Ah battery

BMS, load, charger, capacity monitoring would be none-the-wiser.

 

One concern of that configuration that wouldn't otherwise come up is if one cell in a two-cell pair were to fail.

If the failure is a short, it would bring the other cell with it.

 


From: electricboats@groups.io <electricboats@groups.io> on behalf of ChristopherH via groups.io <clh5_98=yahoo.com@groups.io>

Sent: Wednesday, November 8, 2023 10:34 AM
To: electricboats@groups.io <electricboats@groups.io>
Subject: [electricboats] Parallel LiFePO4 Packs

 

Hi Group,
My Morgan Out Island 41 is ready for new batteries. I'm ready to embrace LiFePO4. When I originally converted to electric I built and glassed in 2 battery boxes to hold 2 banks of 8 (16 batteries) golf cart batteries. I always run with both banks in parallel, but have the ability to run on just 1 and this has worked well. Unfortunately this size battery box doesn't make efficient use of most individual LiFePO4 cells. I would however be able to use 32 X 230Ah EVE cells in 1 battery box, leaving the other box for some other purpose. My questions: I'd like to be able to run the 2 X 16S strings in parallel. Is this possible with LiFePO4? Is it safe to do this? Any precautions? Would I have 2 separate BMS units? How about capacity monitoring for the 2 banks in parallel? I have a Victron 48V/5KVA Victron Quattro charger inverter. 
Thanks in advance for any assistance/suggestions.

Regards,
Chris Hudson

Sent from myPhone