T-Pain Is On A Boat: RE: [Electric Boats] Battery Charging with and without a charger

Saturday, April 24, 2010

RE: [Electric Boats] Battery Charging with and without a charger

Thanks Mike,

I’m somewhat concerned about how the batteries are protected during charging off the Genset. The problem is the Voltage gauge shows what is being supplied by the genset not what the batteries would currently be charged to, that the charging is being unregulated with no regulator (other than me?). Maybe it is being regulated by me setting the output of the generator at the rheostat of the Genset control board. I’m also assuming that the distribution box is pumping back to the batteries from the genset without going through the charger. Since the motors are connected at this point also, the feed from the genset being 164v, I’m somewhat concerned about running the motors at 164v instead of the 144v they were designed to. That may be a good question for Solomons the motor manufacturer. I’ll check with them. There are 2 controllers per motor, maybe that’s the point that smoothes out any power difference. One other note. Today the power was off at the dock so I thought it would be a good time to check out a few things. I ran the genset and started to crank up the rheostat to 164v. The Output amp gauge stayed at 0 A/C amps. This was with nothing running and the batteries down around 152v. I started up the motors and throttled up and the A/C amp gauge came off 0A and up to around 5A’s I didn’t want to tear the end of the dock off :o) so didn’t throttle up much but it showed the power was going to the motors as well as the batteries went up to around 159V. This is what I was hoping for, it’s just the previous time it pegged the A/C amp gauge that has me scratching my head.

I’ll continue to try recreate the scenario until I get this figured out.

Thanks,

Steve

From: electricboats@yahoogroups.com [mailto:electricboats@yahoogroups.com] On Behalf Of Mike
Sent: Saturday, April 24, 2010 6:22 AM
To: electricboats@yahoogroups.com
Subject: Re: [Electric Boats] Battery Charging with and without a charger

Steve:

Without seeing the system it does sound like the generator is connected to the battery bank directly. I'm guessing that sometimes you may be operating under the current limits of the generator and you so are seeing 60 amps. At other times you may be drawing max current from the generator and tapping into the batteries as well. It sometimes does not take to much more speed to increase the current demand. So even after you shut things down the generator is still bulk re-charging the battery bank. You might also have a failing battery. The Paktrakr will really help in seeing what the individual batteries are doing.

Capt. Mike

http://biankablog.blogspot.com

--- On Fri, 4/23/10, Steve Dolan <sdolan@scannersllc.com> wrote:

From: Steve Dolan <sdolan@scannersllc.com>
Subject: [Electric Boats] Battery Charging with and without a charger
To: "electricboats@yahoogroups.com" <electricboats@yahoogroups.com>
Date: Friday, April 23, 2010, 11:29 AM

Capt. Mike and others,
This scenario is interesting maybe you could shed some light on an issue I've been having or at least point me in a direction.
My Cat has a 144v system with a 16kw Genset. I have a BRUSA charger that charges at a max rate of 35A. There is a distribution box that output from the batteries goes to and output from the Genset goes to. The output from the genset is also 144v DC at 80A. The Genset has a variable output, I can set the Voltage at anything I want, typically it's set at 164v which is a safe setting for the batteries, 12,12V. I have 2 Solomons Electric Motors that I normally run at about 30A each for a total load of 60A on the 144v bank plus the "extras" on 3 12v house batteries. I have a Voltage gauge to indicate the state of charge of the batteries as well as an A/C AMP output gauge (prior to being rectified)for the Genset.

So here's my mode of operation.
Head out under power for approx. 45 minutes sail for the next say 6 hours and notice my batteries are down to 150v. Start the genset up and engage the generator then set the output for the genset to 164v and watch the A/C Amp gauge swing up to say around 60A. Charge until the A/C amp gauge output is down to around 10A then shut the genset down.

Does this sound correct?

So every once in a while this happens.

Head out under power for approx. 45 minutes sail for the next say 6 hours and notice my batteries are down to 150v. Start the genset up and engage the generator then set the output for the genset to 164v and watch the A/C amp gauge peg above 80A then fall off to 0. Even if I set the Voltage to 0 and shut the motors off the genset still pegs the Amp gauge. It's almost like the Battery bank is sucking all the power out of the Genset.

Does this make any sense?

I purchased the boat with the system installed. I've been spending the last few months creating wiring diagrams that the builder didn't provide and I'm just now getting to the main circuits and trying to figure out how the power from the generator is being sent to the batteries. I don't think the genset is going through the Brusa Charger at this point since its set up for shore power and at 240v where the genset is outputting 144v so my guess is that it's shoving 144v directly to the batteries at the distribution box. By the way I just ordered the Paktrakr and Powercheq systems to install. Monitoring is gooood!

Is this a correct assumption?

Any help with this is greatly appreciated and if anyone has any questions I'll try and answer.

Thanks,
Steve

Mike,

So you just unplugged the charger then reconnected and it started charging again? That's good to know. I would guess the "time-out" time period would be information the charger manufacturer should have. Knowing that you should be able to cycle through off/on regularly and have no interruption in power. Right?

Mark

--- In electricboats@ yahoogroups. com, Mike <biankablog@ ...> wrote:
>
> "Another thing to consider is what happens to your charger if you use it
> as a power supply. For example, you run your generator to feed your
> charger and motor the boat under electric power without drawing down the
> batteries. Not all chargers can handle this type of usage. Some
> chargers will believe there is a battery fault if they are running at
> 20A all the time. They expect the "batteries" to eventually get full
> and they apparently never do. I think Mike from
> http://biankablog. blogspot. com can expand more on this from his experience."
> Â
> Â
> I believe Jason is right about the battery chargersÂ "going dumb" on occassion. I was doing some extended motoring using my ZIVAN NG-1 and running it flat out with the Honda 2000 providing power. At the time I did not have a functioning current meter so I was cruising along when several hours later I began to notice that the battery bank voltage was dropping but, the Zivan charger still had a green light. So I kept moving along.Â When the battery bank voltage hit 48 volts I figured there was some kind of problem. I disconnected the Zivan from the Honda generator and reconnected it and the chargerÂ started to charge again (red light = bulk charge). If I had a functioning current meter I would have noticed that the battery charger had gone into a fault mode much sooner andÂ reset of the charger earlier which would have prevented the increased draw down of the battery bank. I have since been able to repair the defective current meter
> http://biankablog. blogspot. com/2009/ 12/going- electric- repairing- zantrex-xbm. htmlÂ I have also added the current probe to my Paktraker meter so I have two places to keep an eye on current draw from the battery bank.Â IMO it's important diagonostic tool that justifies having a backup place to read the current.
> Â
> Capt. Mike