Electrical problem

[snadd1s]

Hello,
I have a Bene 473 and this is what happens;
When under motor or inshore el power connected, all is normal.
However, when under battery power only ( even with all switches off on the control panel) the Amp meter "peaks" ( from 1-10 times pr.min) to about 15 Amps with subsequent drop in the Voltmeter. This makes my Raymarine navsysten to trip and restart.
Batteries are tested to be ok.
Any ideas folks?

 

[Don S/V ILLusion]

Hard to guess but an intermittent bad connection would cause high resistance indicative of your description.

 

[centerline]

it may be happening with charge voltage going in to it as well, but you just dont notice it due to the higher amp influx... which would be extremely hard on a charging system.

can you hear any slight click of a circuit breaker?

you could have a bilge pump switch failure/short, as these are sometimes not ran thru switches that can be turned off.
but then your raymarine unit is obviously not ran thru a switch either, or it would be off with all the switches.

if all devices and electronics ARE ran thru switches, in most cases its an easy task finding what circuit is causing the problem.

you need to identify what devices are NOT connected thru the panel switches and troubleshoot each one individually.

a short circuit tester would make short work of the problem, or an old inductive style amp gauge.... which is what the analog short circuit testers are based on... hold it near the wire and follow it along and watch the meter bounce until you find the problem.

its possible that someone may have installed a bilge pump or other device without a fuse inline, which is irresponsible, but it happens... an internal circuit breaker from a failed device could be causing the issue...

once you find the individual circuit that is causing the problem, it will likely be an easy fix.

 

[Paul Mermelstein]

Is the inverter On when this happens?

 

[snadd1s]

Hello all,
thanks for reply,
the strange thing is that when everything is switched off ( by the switches on the control panel) its still happening. The only thing that is on, is the main battery. - but as mentioned, everything is switched off. The main batteries are checked and they are still good

 

[Davidasailor26]

If you can see the amp meter spike when all of the switches are off then there must be some sort of load shorting after the amp meter that's not controlled by the breakers. Bilge pump is a good guess. Otherwise I wonder where in your circuit the amp meter is?

 

[Philip_Oceanis 361]

This is just a thought. Some years ago I had all sort of crazy problems with my electrics. Batteries showing low voltage while they were full, sudden loss of electricity at engine panel after turning off the engine (and then it was on just by itself after some time) and so on. It was driving me crazy and took me some months to find out what caused all these problems. And the reason...just a bad connection of the alternator negative. Yes, just this little - few seconds to fix - problem. So, who knows check the alternator as well as the engine negative connections. You never know.

 

[snadd1s]

I found out why the amp meter peaks...
Something as stupid as the "electronic antifouler"
With that disconnected, the amp meter behaves normal. My problem still persists though...

 

[Syversens]

Hmmm, is that like an ultrasonic antifouling so you do not have to apply bottom paint? I've seen those at boat shows and quite interested in your experience with it, other than this of course....

I'm thinking a switch so you can turn that off while at anchor be a good idea, unless you spend more time at anchor than at dock.