Stray DC current

yooper
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Stray DC current

Postby yooper » Sun Jul 23, 2017 1:28 pm

I was testing the voltage at the distribution panels for the lower helm by switching the breakers on and off. The shower pump terminal still read .13 volt with the breaker switch off. The stereo terminal read .47 volt with the switch off. What's going on? After 29 years are the old airpax breakers starting to leak? I got some new spares and will try them. Stand by.

Fastjeff
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Re: Stray DC current

Postby Fastjeff » Sun Jul 23, 2017 6:25 pm

Electrical problems! Arrgh!

Looks like you'll have to pull one wire at a time until you find the leaker.

The memory circuit in the radio (music) on mine was drawing .03 amps with the ignition off, and that was enough to kill the battery overnight.

Jeff
"We live at the bottom of an ocean of air, not at the top." General Marvage Slatington

martindesign
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Re: Stray DC current

Postby martindesign » Mon Jul 24, 2017 5:04 pm

.3 amps? .03 shod not run down a battery for weeks
Machanic, fabricator, carpenter, plumber, electrician, designer, hotrod builder and glutton for punishment. :ugeek: current boat; 1969 Marinette 32 express bridge 440's
Catawba Oh

honestcharlie56
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Re: Stray DC current

Postby honestcharlie56 » Mon Jul 24, 2017 7:22 pm

tell us about your volt meter
1990 Marinette 32 Sedan Flybridge "Hubba" Lake Charles, LA
Twin Chrysler 318's

BlueSkye
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Re: Stray DC current

Postby BlueSkye » Tue Jul 25, 2017 6:30 pm

One suggested reality check is to measure the resistance across the breaker with the wires disconnected, if you have a multimeter.
1971 32ft Express 2x318
Seneca Lake, Erie Canal, Lake Ontario, Rideau

Fastjeff
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Re: Stray DC current

Postby Fastjeff » Thu Jul 27, 2017 5:58 pm

...".03 should not run down a battery for weeks"

Overnight! And twice. And with deep discharge batteries! Beats the hell out of me how that can happen, but... Put a charger on them and they bounce back very quickly.

Jeff
"We live at the bottom of an ocean of air, not at the top." General Marvage Slatington

martindesign
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Re: Stray DC current

Postby martindesign » Wed Aug 02, 2017 8:10 pm

Jeff. Something else must be going on. That's about 1/3 watt. I'd love to see a load test on the batteries or if something is kicking on overnight that is a heavier load? Very odd.
Machanic, fabricator, carpenter, plumber, electrician, designer, hotrod builder and glutton for punishment. :ugeek: current boat; 1969 Marinette 32 express bridge 440's
Catawba Oh

Fastjeff
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Re: Stray DC current

Postby Fastjeff » Thu Aug 03, 2017 6:20 am

Gotta tell you a story: Years ago the family and I were watching fireworks from our car. The motor was off, but something was still on and ran the battery down (in a 1/2 hour). It was so low that the solenoid only went 'click' (the dreaded click). Called my good buddy Hoppy who came out to jump the battery.

Here's where it gets interesting. I could see him attaching the jumper cables, and soon as they were on I hit the key. The motor exploded into life, cranking over as if the battery was fully charged, yet it has so little juice before then the headlights barely lite, and the solenoid only 'clicked'.

How is that possible? You tell me, but I've seen these 'modern' batteries do this nonsense many times.

Jeff
"We live at the bottom of an ocean of air, not at the top." General Marvage Slatington

martindesign
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Re: Stray DC current

Postby martindesign » Thu Aug 03, 2017 7:04 am

Well, in theory if jumper cables have good contact it will instantly fire up and then act normal from alternator even with a totally bad battery. With that said, batteries sometimes loose just one cell which can do odd things. Best way to check it is do a proper load test on them when fully charged. If .03 is genuinely your only parasitic draw than I would lean towards a bad cell in the battery.
Machanic, fabricator, carpenter, plumber, electrician, designer, hotrod builder and glutton for punishment. :ugeek: current boat; 1969 Marinette 32 express bridge 440's
Catawba Oh

BlueSkye
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Re: Stray DC current

Postby BlueSkye » Thu Aug 03, 2017 10:36 am

How is that possible?

I would suspect a bad connection between your battery cable and terminal.
1971 32ft Express 2x318
Seneca Lake, Erie Canal, Lake Ontario, Rideau