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Tripping Circuit Breaker

threepets

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I have activated my MPP LV 6548 Solar system . Everything runs great until off grid charging is called for. After 15 or so minutes the off grid circuit that has been called upon to charge the battery trips . I have tried 2 different circuits and the same thing happens...Breaker trips. The cable I am using from Inverter to the off grid plug is 10/3 is that to light of Cable? Could that be the problem ? 15 Amp Breaker on the circuit.
 

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Inverter/chargers do one or the other, not both at the same time.

When charging from AC, the inverter is passing that AC through to the loads, so loads + charging must not exceed 15A input from that circuit.

In other words, your loads + charging must not exceed 15A * 120V = 1800W. If you exceed 1800W in loads and charging, you will pop the breaker.

Your AC input must be powerful enough to handle loads and charging, i.e., 6500W in loads and say 1500W in charging (30A) or 8000W total.

This is how all of these things work. You would have the same problem if you were using a Magnum, Victron, Schneider, etc.

Your only real option is to get a suitable 48V charger powered by the 15A circuit and connected to the battery. You would likely need a secondary solution to automate charging.

EDIT: While it's not stated explicitly, the manual indicates a lot of AC input is required. It suggests 4awg for AC input and a 60A breaker. It also states a 60A max AC input current in the specs.

Essentially, this is telling you that you need to feed your unit with 60A to allow for passthrough and charging.
 
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User settings menu item #11 "Maximum Utility Charging Current" has to be set for less than 30A otherwise the AC input will draw more than the 15A breaker can supply. Try setting it at 20A and see if that solves the problem.
Also, check the breaker to make sure its not getting hot.
 
Inverter/chargers do one or the other, not both at the same time.

When charging from AC, the inverter is passing that AC through to the loads, so loads + charging must not exceed 15A input from that circuit.

In other words, your loads + charging must not exceed 15A * 120V = 1800W. If you exceed 1800W in loads and charging, you will pop the breaker.

Your AC input must be powerful enough to handle loads and charging, i.e., 6500W in loads and say 1500W in charging (30A) or 8000W total.

This is how all of these things work. You would have the same problem if you were using a Magnum, Victron, Schneider, etc.

Your only real option is to get a suitable 48V charger powered by the 15A circuit and connected to the battery. You would likely need a secondary solution to automate charging.
Thank you ,for helping me with this issue.
 
User settings menu item #11 "Maximum Utility Charging Current" has to be set for less than 30A otherwise the AC input will draw more than the 15A breaker can supply. Try setting it at 20A and see if that solves the problem.
Also, check the breaker to make sure its not getting hot.
Thank You
 
That depends on what's supplying it. Given that you're using 10/3 wiring, the answer is yes. 10/3 can handle 30A; however, you have to trace it all the way back to the source. All wiring and breakers between the source and inverter must be able to support the current.
Thank You.
 
That depends on what's supplying it. Given that you're using 10/3 wiring, the answer is yes. 10/3 can handle 30A; however, you have to trace it all the way back to the source. All wiring and breakers between the source and inverter must be able to support the current.
Could I give the inverter a dedicated 30 Amp circuit?
I was going to increase the cable size to 6 AWG as well.
I am hoping this something I am not going to require on a regular bases (Grid supply charging) but today the weather forecasts 5 days of cloud cover.
 
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Could I give the inverter a dedicated 30 Amp circuit?
I was going to increase the cable size to 6 AWG as well.
I am hoping this something I am not going to require on a regular bases (Grid supply charging) but today the weather forecasts 5 days of cloud cover.
The inverter can handle a breaker of 50A and 6AWG wiring would support that also. The more important question is what is the capacity of the breaker panel being used to feed power to the inverter AC input. Is it already up to its limit or can a 30A breaker be added safely? If you are only using a 30A breaker then 8AWG wire is all you need.
 
Could I give the inverter a dedicated 30 Amp circuit?
I was going to increase the cable size to 6 AWG as well.
I am hoping this something I am not going to require on a regular bases (Grid supply charging) but today the weather forecasts 5 days of cloud cover.

While this may improve things, you are still limiting your output and may experience issues. 30A @ 120V is only 3600W, so loads + charging must be < 3600W.
 
Using the 80% rule, should be <2880 watts continuous.
The only load I have on the system when it charges ,so far, is the actual charging of the 5.12 KWh Battery. Where do I find the required charging information for my Battery
 
The only load I have on the system when it charges ,so far, is the actual charging of the 5.12 KWh Battery. Where do I find the required charging information for my Battery
What battery do you have?
 
Please provide a product link to your battery.
 
The battery information is under the description header at the link you provided.
Code:
Nominal Voltage: 51.2 V
Nominal Capacity: 100 Ah
Dimension (LxWxH): 19" x 17" x 8.6″ (482mmx430mmx221mm)
Approx. Weight: 100 lbs ( 45 Kg )
Capacity @ 20A 300 min
Energy: 5120 Wh
Resistance: < 50mΩ
Self Discharge: < 3%
Cells: 3.2V 100Ah Cells
Recommended Charge Current: 50 A
Maximum Charge Current: 100 A
Recommended Charge Voltage: 58.4 V (3.65 V/Cell)
BMS Charge Cut-Off Voltage>  59.2 V (3.7 V/Cell)
Reconnect Voltage < 54.08 V (3.38 V/Cell)
Balancing Voltage > 54.4 V (3.4 V/Cell)
Maximum Continuous Dishcarge Current 100 A
BMS Discharge Current High Warning 125 A
BMS Discharge Cut-Off Current 130 A (1000ms)
Low Voltage Warning 44.8 V ( 2.8 V/Cell*16)
BMS Discharge Cut-Off Voltage <40 V (1 s) ( 2.5 V/Cell*16)
Reconnect Voltage >46.4 V ( 2.9 V/Cell)
Short Circuit Protection 300 μs
Terminal Type M8x4
Terminal Torque 106 ~ 132 in-lbs ( 12 ~ 15 N·m )
Case Material: Steel
Recommended Connection Wire: 6 AWG
Temperature Sensor Quantity: 6 pcs
Discharge Temperature:– 4 ~ 140 °F ( – 20 ~ 60 °C )
Charge Temperature– 23 ~ 131 °F (  0 ~ 55 °C )
Storage Temperature– 23 ~ 95 °F (  0 ~ 35 °C )
BMS High Temperature Cut-Off 149 °F ( 65 °C )
Reconnect Temperature 140 °F ( 60 °C)
 
Here are the relevant bit IMO.
The indented lines indicate changes from the default
Code:
Nominal Voltage: 51.2 V
Nominal Capacity: 100 Ah
Energy: 5120 Wh
Cells: 3.2V 100Ah Cells
Recommended Charge Current: 50 A

Recommended Charge Voltage: 58.4 V (3.65 V/Cell)
    Recommended Charge Voltage: 56.8 V (3.55 V/Cell)

BMS Charge Cut-Off Voltage>  59.2 V (3.7 V/Cell)
    BMS Charge Cut-Off Voltage>  58.4 V (3.65 V/Cell)

Reconnect Voltage < 54.08 V (3.38 V/Cell)
    Reconnect Voltage < 49.6 V (3.1 V/Cell)

Balancing Voltage > 54.4 V (3.4 V/Cell)

Low Voltage Warning 44.8 V ( 2.8 V/Cell*16)
    Low Voltage Warning 48.8 V ( 3.05 V/Cell*16)

BMS Discharge Cut-Off Voltage <40 V (1 s) ( 2.5 V/Cell*16)

Reconnect Voltage >46.4 V ( 2.9 V/Cell)
    Reconnect Voltage >48.8 V ( 3.05 V/Cell)

Recommended Connection Wire: 6 AWG
    Recommended Connection Wire: 4 AWG

BMS High Temperature Cut-Off 149 °F ( 65 °C )
Reconnect Temperature 140 °F ( 60 °C)
 
The thing that isn't indicated is float voltage.
I suggest to float no higher than 53.6 volts(3.35 per cell).
 
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