diy solar

diy solar

Dead Victron MPPT, unlucky or?

dania02525

New Member
Joined
Dec 25, 2022
Messages
9
Hello all, I've set up a very modest system in my travel trailer, and the first time I wired all three panels to my 100/50MPPT, the unit charged my battery at 25 amps and then died.

I received a replacement from current connected immediately, credit to them, but I just wanted to verify my set up here so I don't have issues with the replacement and or can confirm I just got unlucky.


Solar: 3x 200w rich solar wired in series with 50ft of awg10 wire, connected through an Anderson style connector, then direct to the victron 100/50 MPPT
Battery: 1 SOK 206AH LiFE
Charger: Victron IP67 25amp
Inverter: Victron phoenix 1200VA


I have a 100amp main breaker to protect the battery, a 60 amp breaker between MPPT and bus bar. I double checked for 12v, correct polarity at the battery terminals of the MPPT, and checked polarity and open voltage of the panels before plugging them in, ~63v.


The first MPPT worked just fine on Bluetooth before connecting the solar, and seemed to be charging the battery at around 25amps for 10 minutes before shutting down completely, no lights, no Bluetooth. disconnecting for 5 minutes didn't reset it either. Anything I should check out more before connecting all three panels to the replacement unit?
 
Do you still have power on the battery terminals on the MPPT?

It might be as simple as a fuse between the battery and the MPPT which has blown. (Should be a 60-70A fuse, and off course wires able to handle that). And you don't happen to have a crappy black/red breaker which has failed as 'fuse'?
 
Yes, had full battery voltage at the MPPT, 60A mini breaker was closed. I'm using the Tocas breakers recommended by will, and it seems to be working fine.
 
I've actually since put the replacement unit in, which works fine so far and charges the battery off one panel. The problem didn't surface before until all three panels were in full sun though (waiting for the sun to come back out here to test)
 
I'm not so sure about those breakers. Did you measure the voltage drop, and confirmed that was the issue getting no charge at all? Even without solar it should still power the MPPT.

If its a 60A rated breaker and appearantly failed at <50A it's just a typical example of a crap breaker. They should never trip even with 60A. At 70A, they should eventually trip, but not instantly.

I would bin the replacement as well and just install a proper MIDI fuse of 60-70A.
Or invest in a quality breaker from eg Bussman or BlueSea systems, eg https://www.walmart.com/ip/Blue-Sea-285-Series-60-Amp-Circuit-Breaker-Surface-Mount/35656829
 
Hello all, I've set up a very modest system in my travel trailer, and the first time I wired all three panels to my 100/50MPPT, the unit charged my battery at 25 amps and then died.

I received a replacement from current connected immediately, credit to them, but I just wanted to verify my set up here so I don't have issues with the replacement and or can confirm I just got unlucky.


Solar: 3x 200w rich solar wired in series with 50ft of awg10 wire, connected through an Anderson style connector, then direct to the victron 100/50 MPPT
Battery: 1 SOK 206AH LiFE
Charger: Victron IP67 25amp
Inverter: Victron phoenix 1200VA


I have a 100amp main breaker to protect the battery, a 60 amp breaker between MPPT and bus bar. I double checked for 12v, correct polarity at the battery terminals of the MPPT, and checked polarity and open voltage of the panels before plugging them in, ~63v.


The first MPPT worked just fine on Bluetooth before connecting the solar, and seemed to be charging the battery at around 25amps for 10 minutes before shutting down completely, no lights, no Bluetooth. disconnecting for 5 minutes didn't reset it either. Anything I should check out more before connecting all three panels to the replacement unit?
Please don't discard the old/failed Victron MPPT. It may be repairable. Reverse polarity during installation or overvoltage/overcurrent will damage the MPPT. Cheap quality external fuse/breaker can also be the culprit. What is the detail spec of the panel? is this 12V battery?
 
Just thinking out-loud...is your "Anderson style connector" rated for that current?
I know some Anderson stuff isn't.
 
How are the panels configured, as in 3 in series or 3 in parallel?
What are the panel specs?
Their is usually a placard on the back of the panel that has all the details.
 
Your breakers may be a problem with unreliable operation, volt drops and other issues. Unless you are prepared to use expensive quality items, fuses are a recomended alternative.
100 amp protection on the battery is too low for a 1200 VA inverter, suggest a MRBF fuse at at least 150 amps with suitable rated cable.
Fuse the solar controller at 75 amps.

It's not clear how you deduced the charger had died. A common issue with SOC batteries is that due to the use of too high a charge voltage, cell overvolts occurs and the BMS shuts down the charge path.

Mike
 
The Anderson connectors I have are rated at 50 amps. No voltage drop across the breaker, because there is no load. The voltage at the MPPT was the same as at the battery, and same as at the bus bars. The MPPT stopped showing any lights and stopped broadcasting Bluetooth. The BMS has not shut down on the battery because I'm monitoring it on my BMV-712.


The panels are in series, and are 20.4v vmp, 24.3v open circuit, 9.8amp max current.


I'm using the 100amp breaker because I need only a minimum of current. I'm aware the inverter can pull more than what the breaker is limited at, but the battery is an SOK 206ah 12v and is rated for 100amps continuous maximum. The idea is that I might later connect a couple more batteries in parallel, while for now the inverter will just be used for charging laptops and running an AC fan.


I don't believe I have drawn too much current or overvolted the MPPT, since I didn't have any loads on at the time I was testing it, and I was connected to the MPPT via Bluetooth and monitoring at at 25amps charging. I checked at the Anderson plugs too to ensure correct voltage and polarity before plugging in the panels.
 
I'm not so sure about those breakers. Did you measure the voltage drop, and confirmed that was the issue getting no charge at all? Even without solar it should still power the MPPT.

If its a 60A rated breaker and appearantly failed at <50A it's just a typical example of a crap breaker. They should never trip even with 60A. At 70A, they should eventually trip, but not instantly.

I would bin the replacement as well and just install a proper MIDI fuse of 60-70A.
Or invest in a quality breaker from eg Bussman or BlueSea systems, eg https://www.walmart.com/ip/Blue-Sea-285-Series-60-Amp-Circuit-Breaker-Surface-Mount/35656829

I had full battery voltage at the MPPT, and it was unresponsive. I also couldn't wake it up bench testing with a lead acid battery I had laying around. The replacement unit has been connected to the battery for a few days and works fine via Bluetooth. I will connect the three panels series once again when the sun comes out again
 
The Anderson connectors I have are rated at 50 amps. No voltage drop across the breaker, because there is no load. The voltage at the MPPT was the same as at the battery, and same as at the bus bars. The MPPT stopped showing any lights and stopped broadcasting Bluetooth. The BMS has not shut down on the battery because I'm monitoring it on my BMV-712.


The panels are in series, and are 20.4v vmp, 24.3v open circuit, 9.8amp max current.


I'm using the 100amp breaker because I need only a minimum of current. I'm aware the inverter can pull more than what the breaker is limited at, but the battery is an SOK 206ah 12v and is rated for 100amps continuous maximum. The idea is that I might later connect a couple more batteries in parallel, while for now the inverter will just be used for charging laptops and running an AC fan.


I don't believe I have drawn too much current or overvolted the MPPT, since I didn't have any loads on at the time I was testing it, and I was connected to the MPPT via Bluetooth and monitoring at at 25amps charging. I checked at the Anderson plugs too to ensure correct voltage and polarity before plugging in the panels.
What is the temperature around the panels? ambient temp.
 
The Anderson connectors I have are rated at 50 amps. No voltage drop across the breaker, because there is no load. The voltage at the MPPT was the same as at the battery, and same as at the bus bars. The MPPT stopped showing any lights and stopped broadcasting Bluetooth. The BMS has not shut down on the battery because I'm monitoring it on my BMV-712.


The panels are in series, and are 20.4v vmp, 24.3v open circuit, 9.8amp max current.


I'm using the 100amp breaker because I need only a minimum of current. I'm aware the inverter can pull more than what the breaker is limited at, but the battery is an SOK 206ah 12v and is rated for 100amps continuous maximum. The idea is that I might later connect a couple more batteries in parallel, while for now the inverter will just be used for charging laptops and running an AC fan.


I don't believe I have drawn too much current or overvolted the MPPT, since I didn't have any loads on at the time I was testing it, and I was connected to the MPPT via Bluetooth and monitoring at at 25amps charging. I checked at the Anderson plugs too to ensure correct voltage and polarity before plugging in the panels.
Just a thought...If your Anderson connectors are rated at 50 amps and you have a 100amp circuit breaker, under an overload situation wouldn't your Andersons will fail long before your circuit breaker will trip? That would make your Andersons a fuse.
 
Just a thought...If your Anderson connectors are rated at 50 amps and you have a 100amp circuit breaker, under an overload situation wouldn't your Andersons will fail long before your circuit breaker will trip? That would make your Andersons a fuse.

The Anderson's are carrying 60v at 10 amps and far exceed the capacity of the AWG 8 solar wire to the panels. Between the battery and bus bars and inverter, I have AWG 2, and between solar charger and bus bar, and AC charger and bus bar, I have AWG 6. I think it will be helpful if I make a drawing.
 
I do not see VOC ratings. In the right conditions, colder, 3 panels could exceed 100 volt limit of Victron
 
The Anderson's are carrying 60v at 10 amps and far exceed the capacity of the AWG 8 solar wire to the panels. Between the battery and bus bars and inverter, I have AWG 2, and between solar charger and bus bar, and AC charger and bus bar, I have AWG 6. I think it will be helpful if I make a drawing.
Understood. My concern was the circuit's potential current exceeding the Anderson current rating. Large(r) wire is fine, but not good if the wire current capacity is greater than the Anderson current capacity. But, if you have the correct fusing to protect the Anderson capacity then all is good. Well, except you put in higher rated wire than what was needed.
FYI...8AWG can carry up to about 40a continuous, considerably more for short time duration under certain circumstances such as insulation, etc.
 
Understood. My concern was the circuit's potential current exceeding the Anderson current rating. Large(r) wire is fine, but not good if the wire current capacity is greater than the Anderson current capacity. But, if you have the correct fusing to protect the Anderson capacity then all is good. Well, except you put in higher rated wire than what was needed.
FYI...8AWG can carry up to about 40a continuous, considerably more for short time duration under certain circumstances such as insulation, etc.

Yup, I size up the solar wire in case I want to add more panels as a parallel set, that way I can over panel the charge controller and ensure I get the best amperage even in poorer light. I've also got the panels on a 50ft cord to deploy them in the sun, I thing upsizing the wire helps with resistance over a long run. For now with one string, yes, it's oversized.
 
I do not see VOC ratings. In the right conditions, colder, 3 panels could exceed 100 volt limit of Victron
VoC is 24.3v per panel, so less than 75 total in series. I'm in south Florida and testing the panels at 75 degrees ambient, I'm seeing about 20-21v per panel at the end of my 50ft solar wires.
 
VoC is 24.3v per panel, so less than 75 total in series. I'm in south Florida and testing the panels at 75 degrees ambient, I'm seeing about 20-21v per panel at the end of my 50ft solar wires.
Thanks. If it were over voltage , then theVictron app would give an error.
 
Back
Top