FLEXmax 80A always snoozing

Discussion about the FM100, FM80, and FM60 Charge Controllers

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FLEXmax 80A always snoozing

Post by btahir90 » Tue Mar 11, 2014 10:49 pm

sir i installed FM80 charge controller with Selectronics pro series inverter. My charge controller tracks but then shift at snoozing mode. PV voltage is about 83V and Battery voltage is around 51. what should i do to get rid of snoozing. What i see is the setting of float voltage in charge controller is 54V and when tracking PV voltage reduces to the float voltage and then move to snooz mode. shoud i reduce the flot voltage setting?
My charge controller is not grounded and hence not connected to Neutral is it the cause of problem?
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Re: FLEXmax 80A always snoozing

Post by dhamilton » Wed Mar 19, 2014 1:07 pm

It sounds like you panels may not be wired to give you the voltage difference you need for charging your 48vdc battery bank. Make sure your max power voltage is 12-24 volts higher then your charge voltage.

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Re: FLEXmax 80A always snoozing

Post by tallgirl » Sun Mar 30, 2014 3:36 pm


The MPPT voltage needs to be at least 4 volts higher than the temperature-compensated Absorb voltage. For Voc of 83 volts, Vmpp should be more than adequate, even for equalization (except in Texas summers -- Vmpp drops like crazy in the summer here ...).

If the battery voltage is 51, that means you're not discharging. It could be that the batteries are completely and fully charged and the charge controller completed the float time that is programmed. After which, it ... snoozes.
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Re: FLEXmax 80A always snoozing

Post by petertearai » Mon Mar 31, 2014 2:29 am

I know the absorb time can be changed , but didn't realize the float could be timed.
2220 pv. fm80. 12 times 2 volt exc shoto lead carbon 450 AH 24 volts. victron battery monitor. outback fxr 2000 watt inverter

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