EG4 18KPV (EPS Off Grid Overload) Troubleshooting Overload Issues with Hybrid Inverter in Off-Grid Setup

[Scruffydog]

Issue resolved: forgot to check the zero export checkbox under advanced setting.



System Overview:

• Inverters: Two EG4 18KPV hybrid inverters (one primary, one slave)
• Battery Bank: 5x EG4 Power Wall Pro batteries in parallel
• Solar Array: Approximately two pallets of 440W solar panels shared between both inverters
• Power Panel: RV breaker panel with:
• 1x 50-amp 220V plug
• 1x 30-amp 220V plug
• 1x 20-amp 120V GFCI outlet

Issue Description:

• I’ve been using this setup in off-grid mode, and it has worked fine for continuous 300-400W loads on the 20-amp 120V outlet.
• However, I run into problems when connecting my Tesla Universal Portable Charger (UPC) set to 32A on the 220V plug:
• Current Limitation: The inverter maxes out at around 16-17A, even though I’ve set the charger to draw 32A.
• Overload Error: After about 30 minutes, the inverter triggers an off-grid overload (EPS overload) and shuts down.
• Lowering the UPC to draw just 9A still leads to this overload, despite the inverter’s 12,000W continuous rating (which should allow up to 50A at 240V).

Troubleshooting Steps and Observations:

• Time of Day: The overload occurs both during the day and at night, so it doesn’t seem related to solar input.
• System Capacity: The 12,000W continuous capacity suggests it should handle up to 50A at 240V, yet it overloads with far less.

• I’ve tested this same setup on both Inverters independently (on the master or slave inverter) and both inverters still trip the EPS/Off grip overload after a while supplying continuous of 2500-3000W charging the Tesla.
• I have also tried running my central Air conditioner, it was pulling 2200w and I do hear an oscillation struggle but it still kept the condenser running (just not smooth) leaving me think it did not supply sufficient amperage.

If anyone has experience with similar issues or additional suggestions, I’d appreciate the input!

 

[sunshine_eggo]

You say you have two in parallel. Shouldn't you be able to pull 24kW then?

Different manufacturers may use different pallet sizes. A panel count may be more useful if that becomes relevant.

Please see link #2 in my signature.

Wiring parallel inverters together demands that their input and output cabling be equivalent, i.e., you want your L1, N, and L2 wires the same length to the panel.

Hearing that your system appears to struggle with only a 2200W load implies there is some underlying issue with connections.

Leg imbalance can also be an issue. If you are using substantial loads on a single 120V leg, that reduces the 240V available output.

I’ve tested this same setup on both Inverters independently (on the master or slave inverter) and both inverters still trip the EPS/Off grip overload after a while supplying continuous of 2500-3000W charging the Tesla.

This statement is concerning. Are you saying you tried this with each inverter independently with the inverters configured for a single inverter installation, or do you not have their outputs wired in parallel, or have you wired the output of one inverter to one of the 220V plugs and the output of the other to the other 220V plug? If that's the case, this is likely your problem. You should have ONE output to which both inverters are connected. Your plugs should draw from this common outlet.

@EG4TechSolutionsTeam

 

[Scruffydog]

I found out the dumb mistake. I for some reason forgot to check the “zero export” and it fixed the problem.