More questions I'm afraid...
This throttle came with a 3-wire hookup, not two. So the fwd/rev is happening inside the controller (?I think) - a $1.50 rotary pot from Radio Shack worked as a substitute with just the 3 wires hooked up (my goal here is that I can simply sub that pot into my PB-6 after taking out the spring return so that I can use my pedestal throttle lever). And I want more range - so that, for example, 180deg is required to hit full speed vs the 30deg or so that it currently does (does the ohm value effect that? Would a non-linear pot work better?)
Based on http://www.brighthub.com/engineering/electrical/articles/47625.aspx (I otherwise have no idea how the damn thing works :) my guess is the controller is "reading" both of the outer leads on the pot. Therefore, when centered, the resistance is equal from both to the center wiper lead @5K ohm. Rotating off center, the resistance increases on one lead, and decreases on the other and the controller is somehow making sense of that for direction (I may be completely off the mark) Perhaps if I trace the wires, they've simply joined the outer leads as shown in the lower half of reversPOT.jpg (in which case the sensitivity problem is maybe I need a 20Kohm pot??)
The throttle you mention has 5(?) wires - have no clue where those would go...but the datasheet does mention that the analog inputs to the controller can be converted to digital (which is what I'm guessing you have)
I'll check in with TS on Monday, and they can likely lend me some clue as well.
re: Noise - I don't hear the high-pitched whine from the G4 that the PMAC had. Can't tell if my motor is quieter - I never ran it without the belt (intentionally...) before, so nothing to compare to. Also...something may have come loose inside my motor (a bearing race or dust-cover?) as there is a spinning noise that persists for a few seconds after the shaft stops. Just noticed this as I was installing the new controller, but I suspect it was a pre-existing condition.
-Keith
--- In electricboats@yahoogroups.com, "Tom" <boat_works@...> wrote:
>
>
>
> Hi Keith,
> Have a look at the ReversPOT.jpg in the "Controllers" section in "files" of this group. Might be what you need.
>
> I am using a modified Curtis ET-126 throttle (which is now offered already modified by ThunderStruck as the ET-134). Either version requires a relay interface, which is easily homebrewed, to create the required F-R switching.
>
> One of these days I'll also upgrade to the newer G4 controller, hopefully when I choose to, not when I NEED to. :)
>
> Have you noticed the MARS motor running quieter with the G4 controller? Is the G4 quieter "at rest", i.e. contactor energized, but no throttle?
>
> -Tom
>
> --- In electricboats@yahoogroups.com, "aweekdaysailor" <aweekdaysailor@> wrote:
> >
> > Hi,
> >
> > Just installed a new Sevcon controller (don't ask...) and as a result had to put a new wiring harness in (the old Sevcon PMAC's for brushless are EOL btw - if you want spares, now is the time to hunt one up)
> >
> > The new harness came with a (very cheap) slider pot for the throttle, and it's way too sensitive (1/4" in either direction is full speed). Luckily I killed it with corrosion :) so I put a rotary pot in that I happened to have. That works a little better, but still too sensitive, and still exposed to the elements. But, it does fwd/rev without having a separate switch, which is nice.
> >
> > I have my old Curtis PB-6 throttle which I loved because it works off my pedestal's (mechanical) throttle lever and so was out of the elements belowdecks. But it was wired in a way that I had to have a fwd/rev switch in addition to the throttle. It has a 0-5K pot in it and presumably the pot is oriented so that at rest it's at zero. If I just rotate that pot 90 degrees (so that zero is now center of the range) - will that give me the fwd/rev I need? Is it OK to use a 5K pot instead of a 10K? (fwiw I think the old controller spec'd a 10K pot as well...but it came with the 5K)
> >
> > thx
> >
> > -Keith
> >
> > BTW - the new controller doubled regen - I can get almost 2amps (100watt) in bursts (I asked thunderstruck to drop the braking force quite a lot - maybe it's that, or just the new controller is more efficient)
> >
>
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