Sentry charger not turning on automatically
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Sentry charger not turning on automatically
My charger light is showing batteries are fully charged but they aren't. I'm showing 11.0 v on vom. I can turn the charger to manual and it charges normally and the full charge light goes off as it should. The starboard starting battery is fully charged but the port is the one that isn't. That's my house battery for bilge pumps. Is there a sensor that can go out on each bank that tells the charger to kick on? The model is Sentry 12v 60amp FR Series.
- WayWeGo
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Re: Sentry charger not turning on automatically
I think the Sentry chargers are ferromagnetic chargers that have a turn-on (12.8V) and a turn-off (13.9V) voltage with no trickle charge. Since you can manually charge that battery, it seems likely there is a relay that is working but the low voltage sensing circuit is not working for that bank.
Sentry chargers are made by Linear Devices Corporation and you can reach them at 1-888-532-8768.
It might be worth it to switch the leads between the port and starboard to make sure the problem follows the charger rather than the battery.
Maybe you can have it repaired or replace it with a more modern charger. We have a 30A ProNautic charger that I have been pleased with so far -- it was installed a year ago and is doing a great job with our three AGM battery banks.
Sentry chargers are made by Linear Devices Corporation and you can reach them at 1-888-532-8768.
It might be worth it to switch the leads between the port and starboard to make sure the problem follows the charger rather than the battery.
Maybe you can have it repaired or replace it with a more modern charger. We have a 30A ProNautic charger that I have been pleased with so far -- it was installed a year ago and is doing a great job with our three AGM battery banks.
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Twin Chrysler 440's
- P-Dogg
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Re: Sentry charger not turning on automatically
I have pronautic 12p40. I love it. Changing to a smart charger will make your batteries last longer, and is one of the few improvements that will make the boat lighter.
Last edited by P-Dogg on Tue Dec 06, 2016 8:09 pm, edited 1 time in total.
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- prowlersfish
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Re: Sentry charger not turning on automatically
P-Dogg wrote:I have pronautic 12p40. I love it. Changing to a smart charger will make your batteries last longer, and is one of the few improvements that can make that will make the boat lighter.
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77/78 TROJAN F36 Conv.
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77/78 TROJAN F36 Conv.
6BTA Cummins diesels
Life is to short for a ugly boat

Re: Sentry charger not turning on automatically
I agree. Before you jump to the conclusion that it's a charger problem, check the other possibilities such as bad connections, and load test the battery.WayWeGo wrote:.....It might be worth it to switch the leads between the port and starboard to make sure the problem follows the charger rather than the battery.....
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And thanks to the gang, 2012 Trojan Boater Of The Year