100amp Epever MPPT reset

[Traveler2017]

New to the forum and solar power. My SCC (100amp Epever MPPT) shows I'm getting voltage (40+) from two 390w bi-facial panels but shows no amps from SCC to batteries (12v AGMx2). Tested panels on the roof of RV with clamp meter and showing volts and amps. The positive cable from SCC to batteries was evidently not tight enough as it came loose (pulled out of SCC) while panels were putting out mid-day. Also at this time, we were plugged into shore power. I have a 50amp breaker switch between the panels and the SCC with a 150amp fuse between the batteries and the inverter and a 30amp fuse between the SCC and batteries, none of which tripped or blew. I have read that the charge controller can be reset, but there is no reset button. I'm not sure of the sequence for disconnecting and reconnecting the cables to do a reset and the owners manual(?) doesn't reference any type of reset. The fuse in the controller tests good. If the SCC HAS been damaged, can it be repaired, and if so where and/or how? Any help would be appreciated. Thanks in advance.

 

[Bud Martin]

New to the forum and solar power. My SCC (100amp Epever MPPT) shows I'm getting voltage (40+) from two 390w bi-facial panels but shows no amps from SCC to batteries (12v AGMx2). Tested panels on the roof of RV with clamp meter and showing volts and amps. The positive cable from SCC to batteries was evidently not tight enough as it came loose (pulled out of SCC) while panels were putting out mid-day. Also at this time, we were plugged into shore power. I have a 50amp breaker switch between the panels and the SCC with a 150amp fuse between the batteries and the inverter and a 30amp fuse between the SCC and batteries, none of which tripped or blew. I have read that the charge controller can be reset, but there is no reset button. I'm not sure of the sequence for disconnecting and reconnecting the cables to do a reset and the owners manual(?) doesn't reference any type of reset. The fuse in the controller tests good. If the SCC HAS been damaged, can it be repaired, and if so where and/or how? Any help would be appreciated. Thanks in advance.

1) What is your system Voltage? 12V (two 12V batteries in parallel)? or 24V (tow 12V batteries in series)?
2) If the battery cable came out of the Epever while the panels are still connected, it may cause issue, so to reset it you need to disconnect the panels first, then the batteries from the Epever theen let it sit for 1/2 hours and then reconnect the batteries first and then the panels and see what will happen.
3)"we were plugged into shore power" How is the shore power connected to your solar system? Do you have some kind of power transfer switch of some sort?
4) Did the system ever work before?
5) The two solar panels are connected in parallel? correct?
6) What is the spec of the panel?
6) "Tested panels on the roof of RV with clamp meter and showing volts and amps." What is the Amp reading? Were you doing Short circuit current test of the panel? or you are reading the Amp flowing into the SCC?

 

[Traveler2017]

Thank you for such a speedy reply.
1. 12v two 12v in parallel.
3. Shore power powers the converter that charge the batteries, so no, shore power is not connected to solar system.
4. The system was working fine from March thru September
5.Solar panels are connected in parallel.
6. 390W, VOC: 46.8V, VMP: 38.3V, ISC: 10.74A, Max power current: 10.19A
7. Amp reading was10.19 and assume it was amp flow? I borrowed the clamp meter so not really sure.

If I did damage the SCC, can it be repaired? I'd hate to think I just burned up almost $500 worth of gear.

 

[MisterSandals]

SCC (100amp Epever MPPT) shows I'm getting voltage (40+) from two 390w

30amp fuse between the SCC and batteries

This fuse needs to be at least 1.25x what your 100A controller can output (125A).

12V battery, charging at ~14V:
(390W x 2) / 14V = 55.7A So as soon as this SCC gets over 420W, your fuse will blow

Are you certain this fuse is not blown? When you first connect your SCC to the battery, the inverter will start up if the fuse is good.

 

[brum]

The controller reset is just to stop its power (disconnect panels and battery) and reconnect it after a couple of seconds.

Mine has some issues - underestimating the MPP voltage. This happens every few days and the way to reset it is to disconnect the battery and the panels (I have a switch for that). For me, the issue is related to the MPPT algorithm, but the firmware update seems a bit too complicated since I don't have a cable and Windows OS.

 

[Traveler2017]

This fuse needs to be at least 1.25x what your 100A controller can output (125A).

12V battery, charging at ~14V:
(390W x 2) / 14V = 55.7A So as soon as this SCC gets over 420W, your fuse will blow

Are you certain this fuse is not blown? When you first connect your SCC to the battery, the inverter will start up if the fuse is good.

I have another 150 amp fuse I can put in place of the 30 amp. I will do that tomorrow. The inverter is connected to the batteries directly via the 150amp fuse. Did you mean that the controller will start up if the fuse is good? I tested the fuse with an ohmmeter for continuity.

 

[Traveler2017]

1) What is your system Voltage? 12V (two 12V batteries in parallel)? or 24V (tow 12V batteries in series)?
2) If the battery cable came out of the Epever while the panels are still connected, it may cause issue, so to reset it you need to disconnect the panels first, then the batteries from the Epever theen let it sit for 1/2 hours and then reconnect the batteries first and then the panels and see what will happen.
3)"we were plugged into shore power" How is the shore power connected to your solar system? Do you have some kind of power transfer switch of some sort?
4) Did the system ever work before?
5) The two solar panels are connected in parallel? correct?
6) What is the spec of the panel?
6) "Tested panels on the roof of RV with clamp meter and showing volts and amps." What is the Amp reading? Were you doing Short circuit current test of the panel? or you are reading the Amp flowing into the SCC?

Thank you for such a speedy reply.
1. 12v two 12v in parallel.
3. Shore power powers the converter that charge the batteries, so no, shore power is not connected to solar system.
4. The system was working fine from March thru September
5.Solar panels are connected in parallel.
6. 390W, VOC: 46.8V, VMP: 38.3V, ISC: 10.74A, Max power current: 10.19A
7. Amp reading was10.19 and assume it was amp flow? I borrowed the clamp meter so not really sure.
If I did damage the SCC, can it be repaired? I'd hate to think I just burned up almost $500 worth of gear.

 

[Traveler2017]

The controller reset is just to stop its power (disconnect panels and battery) and reconnect it after a couple of seconds.

Mine has some issues - underestimating the MPP voltage. This happens every few days and the way to reset it is to disconnect the battery and the panels (I have a switch for that). For me, the issue is related to the MPPT algorithm, but the firmware update seems a bit too complicated since I don't have a cable and Windows OS.

Thanks for the reply. In what order do you disconnect the battery and panels?

 

[MisterSandals]

Did you mean that the controller will start up if the fuse is good?

Yes, if the fuse is inline between the battery and SCC, it has to be good for the SCC to have power.

Also,
A 150A fuse will support an inverter up to:
150A x 10 inverter cutoff x .85 efficiency = 1275W

 

[Traveler2017]

Yes, if the fuse is inline between the battery and SCC, it has to be good for the SCC to have power.

Also,
A 150A fuse will support an inverter up to:
150A x 10 inverter cutoff x .85 efficiency = 1275W

Thank you, I will swap out the fuses tomorrow. I can only hope it's that simple.

 

[MisterSandals]

Thank you, I will swap out the fuses tomorrow. I can only hope it's that simple.

Start with just the SCC and the battery. Get that working first. If it does not power up, check that you're getting battery voltage at the SCC input terminals.

 

[brum]

Thanks for the reply. In what order do you disconnect the battery and panels?

First, disconnect the panels, then the battery. When connecting them - first the battery, then the pannels.

 

[Traveler2017]

First, disconnect the panels, then the battery. When connecting them - first the battery, then the pannels.

Thank you.

 

[Checkthisout]

That's a nice charge controller. However, they will blow up if you directly connect an ethernet cable from the controller to a PC without using the USB dongle.

So its showing PV voltage and battery voltage on it's display or the MT-50 (remote display) but no chargey? Is that right?

What is the green light on the controller itself doing?

 

[Traveler2017]

Start with just the SCC and the battery. Get that working first. If it does not power up, check that you're getting battery voltage at the SCC input terminals.

Well, I finally got around to swapping the fuses. There is now a 150 amp fuse between the SCC and the battery and still no amps showing on the
SCC display or the MT-50.

 

[Traveler2017]

That's a nice charge controller. However, they will blow up if you directly connect an ethernet cable from the controller to a PC without using the USB dongle.

So its showing PV voltage and battery voltage on it's display or the MT-50 (remote display) but no chargey? Is that right?

What is the green light on the controller itself

 

[Traveler2017]

That is correct. PV voltage & battery voltage on SCC and MT-50 displays, no charge or amps showing. Green light on controller shows steady green.
BTW, there is no connection to a PC.

 

[Traveler2017]

New to the forum and solar power. My SCC (100amp Epever MPPT) shows I'm getting voltage (40+) from two 390w bi-facial panels but shows no amps from SCC to batteries (12v AGMx2). Tested panels on the roof of RV with clamp meter and showing volts and amps. The positive cable from SCC to batteries was evidently not tight enough as it came loose (pulled out of SCC) while panels were putting out mid-day. Also at this time, we were plugged into shore power. I have a 50amp breaker switch between the panels and the SCC with a 150amp fuse between the batteries and the inverter and a 30amp fuse between the SCC and batteries, none of which tripped or blew. I have read that the charge controller can be reset, but there is no reset button. I'm not sure of the sequence for disconnecting and reconnecting the cables to do a reset and the owners manual(?) doesn't reference any type of reset. The fuse in the controller tests good. If the SCC HAS been damaged, can it be repaired, and if so where and/or how? Any help would be appreciated. Thanks in advance.

The basic question of whether the controller can be repaired has not been addressed. Does anyone know if it can be?

 

[Checkthisout]

That is correct. PV voltage & battery voltage on SCC and MT-50 displays, no charge or amps showing. Green light on controller shows steady green.
BTW, there is no connection to a PC.

Triple-check the basics. Did the battery lead get hot before it popped out of the CC? In other words, were there signs of burning on the wire or are there signs of charring/melting on the connection at the controller?

Do you restrip the wires and make sure you have full insertion and haven't just torqued the connections down on nothing?

Take a pic of your connections at the CC and post it here.

If you have GOOD CONNECTIONS, PV voltage showing on the display that is high enough to begin charging and battery voltage showing and a steady green light, then the controller is probably bad.

I would see if you could access the controller with a PC and see what that shows.

In all that, it probably fried when the battery lead popped out while it was in the middle of charging.

 

[Checkthisout]

The basic question of whether the controller can be repaired has not been addressed. Does anyone know if it can be?

Yes but good luck getting anyone at EPEVER to respond. Where did you get it?