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Boat Gauge (Perfect Pass) Cutting Out - Add Capacitor?

jocanon

Member
I just installed a new Perfect Pass (PP) system on my wakeboard boat. For those unfamiliar, PP is like a cruise control for a boat. I have the power to the PP feeding off the power that goes to to the ignition switch so that when the ignition switch is turned on, the PP is on, when ignition is off, PP is off. Everything seems to be working fine, except every once in a while (rarely), the PP system just randomly resets while the key remains in the on position. I think it's because the there might be a bad ground connection in the wiring somewhere, but I do not know where, and I don't even know if that's what it is. I just know the wiring is pretty much a mess back there LOL! Would it be a good idea, just as a band aid (as opposed to searching and finding the bad connection - assuming that isn't practical at the moment), to throw a capacitor in there to even out the voltage drops to the PP system? If so, is it just as simple as finding the right sized capacitor and connecting it to ground and the positive on the power wire feeding into the PP system? Or are there other components I would/should think about adding as well, like diodes or something else to this circuit? Please be nice, I am not an EE and what I am proposing could be a completely idiotic idea and I am OK with you telling me so, just be nice about if you can. :)
 

rjenkinsgb

Well-Known Member
Most Helpful Member
A large value capacitor as close to the PP power connections as possible may help; eg. 10,000uF or more, 25V or 40V rated - one with screw terminals rather than wires, as that will be more reliable in an environment with movement and vibration.

Connect a smaller value plastic film capacitor, eg. 0.1uF, across the large one as well. That can help absorb short "spikes" that big electrolytics don't handle well.

I'd guess there is not a lot of metalwork on a small boat, so grounds are also just wires, anywhere away from the engine etc?

Taking an extra ground directly back to the battery may help things?
 

Tony Stewart

Well-Known Member
Most Helpful Member
The switch current will increase wear if using contacts and a 10,000uF load cap. as the current spike is huge to turn ON (12V/ 12 mohm est = 1000A or 12V/120 mohm = 100A) , but after 1-millisecond switch will certainly filter noise. Contact bounce would make it worse. This could eventually burn the surface of your ignition power switch contacts and wear out prematurely by increasing switch resistance and getting warm..

I would start with a low ESR 10uF metal film cap instead across PP input. Also, use twisted pair wires to PP to reduce radiated noise interference and check results. The idea is to shink the area of the power wire pair and not have a large single wire to battery that makes it like a large loop antenna,.

10uF https://www.digikey.ca/en/products/detail/panasonic-electronic-components/ECQ-E1106KFW/2717607 <<< 10 uF plastic metal film types are low noise, cheap and will protect your switches and reduce noise This will actually improve the quality of your switches by burning off the oxidation layer without burning the silver-nickel alloy contacts. I think this would be a thousand times better if that is your problem otherwise , no effect.
 
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