FM80 woes

Discussion about the FM100, FM80, and FM60 Charge Controllers

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bucketman
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Joined: Wed Jul 28, 2021 4:40 pm

FM80 woes

Post by bucketman »

Driving me nuts .... always sleeping ....

On my 48v system, I've got lots of panels but to keep things simple, I have four 230 watt panels in series. Measuring voltage with no direct sun but still daylight, I get 100 or so volts (analog multimeter). Measured right at the terminals inside the FM80 I also get 100v or so - but the FM80 says 49.6-50.5 or so. I've tried resetting it a couple of times with no success.

Is this unit defective?
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EA6LE-ONE
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My RE system: System 1:
MATE3s, 3 x Radian GS8048A,
6 x FLEXmax 100, HUB10,
2 x EnergyCell 48V 2700RE,
1 x FLEXnet DC, 6 x FLEXware ICS Plus,
78 x PANASONIC VBHN325SA17 325W

System 2:
MATE3s, Radian GS8048A,
2 x FLEXmax 100, HUB10
1 x EnergyCell 48V 2700RE,
1 x FLEXnet DC, 2 x FLEXware ICS
21 x PANASONIC VBHN325SA17 325W
Location: Providenciales, Turks & Caicos Isl.

Re: FM80 woes

Post by EA6LE-ONE »

From what you are describing is sounds like is damaged. You should not turn the PV breaker on before the battery breaker.
raysun
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My RE system: Flexpower Two: (2) FXR3048A-01, (2) FM80, MATE3s, FlexNetDC
SimpliPhi 48-3.8 (6 @ 48v)
Outback IBR3 battery enclosure
REC Alpha 440W panels - 2 arrays: each of 4 strings of 2 in series
Honda EU7000is gas fuel generator

Re: FM80 woes

Post by raysun »

Here's a simple diagnostic to try:
viewtopic.php?f=29&t=14942
bucketman
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Joined: Wed Jul 28, 2021 4:40 pm

Re: FM80 woes

Post by bucketman »

Yeah, good points - I've been super careful to never have the FM80 connected on the PV side alone. Always battery first then PV.

On that diagnostic, it seems like my unit is ok - "out" on the CC is around 50 right now and with the PV side disconnected, "in" voltage looked like it stabilized around 40v or so, which seems like a pass?
raysun
Forum Emperor
Posts: 5624
Joined: Tue Jul 26, 2016 5:57 am
My RE system: Flexpower Two: (2) FXR3048A-01, (2) FM80, MATE3s, FlexNetDC
SimpliPhi 48-3.8 (6 @ 48v)
Outback IBR3 battery enclosure
REC Alpha 440W panels - 2 arrays: each of 4 strings of 2 in series
Honda EU7000is gas fuel generator

Re: FM80 woes

Post by raysun »

I'd think it is OK from that test's perspective.
but the FM80 says 49.6-50.5 or so.
Is this IN or OUT voltage?

If you would be so kind, please fill out your profile with a list of the equipment in the system. Check other's profiles for examples. Having comprehensive info helps us help you. Otherwise, we're flying fairly blind and some key aspect may not occur to you to mention.
bucketman
Forum Junior Member
Posts: 3
Joined: Wed Jul 28, 2021 4:40 pm

Re: FM80 woes

Post by bucketman »

This bit was all about the PV side of the FM80: "Measured right at the terminals inside the FM80 I also get 100v or so - but the FM80 says 49.6-50.5 or so. I've tried resetting it a couple of times with no success" So when the FM80 is reporting 49.6-50.5v, I used my multimeter measured 100v across the PV terminals inside the FM80 - that was really when I started thinking the FM80 was defective, TBH.

For the profile, I'm not sure what to write as I've been paring the system back further and further trying to make the problem simpler. What I'm running right now is the FM80, two 230 watt panels (30v, 9a max, wired in series to yield 60 volts or so), battery bank is 24xUS2200s (232AH, 6v) wired up in 3 strings of 8bateries in series yielding 48v, an epsolar epever 2000w pure sine wave inverter. Wiring is within tolerances the the distance and current. I've got a DC generator connected to the battery bank also - given the FM80 hasn't been working, this is the only thing keeping me in electrons.
fcwlp
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My RE system: GS8048A, FM80 w/3,600W PV Fixed, FM80 w/2,700W on Zomeworks tracker, Mate3, 24 Trojan 2V L16 1100AH @ C20, Grid-Tied with Kohler 14RESA LPG Generator and MEP-803 Diesel if needed.

I install and maintain grid-tied and off-grid systems in my area and consult on solar system design/operation.
Location: 80 miles NE of Phoenix at 5500'

Re: FM80 woes

Post by fcwlp »

Can you post a picture of the FM80 display?
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