Edwin777: Overheating terminal on AIMS AC Inverter DC input

This discussion was created from comments split from: MPPT Tristar 60 - Positive terminal burning.


  • Edwin777
    Edwin777 Registered Users Posts: 1
    Similar is been my problem, AWG 4 cable going from my  Aims MPPT 100 amp charger controller in the conector block for the +ve terminal burn out. I took the charger controller for warranty the terminal  block was replaced but the excessive of heat came back , my question is do I need specific or special breaker to prevent or the AIMS Controller is the problem 
  • BB.
    BB. Super Moderators, Administrators Posts: 33,476 admin
    Welcome to the forum Edwin,

    I have moved your questions to your own "discussion". That way the Q&A only applies to your situation.

    From this link for AWG vs Ampere rating for wiring (simplified NEC wiring chart):


    is rated for 70-95 Amps (depending on wiring insulation type, ambient temperature, etc.)--So, if, you are  pushing 100 Amps through the 4 AWG wiring--It is going to run "warm".

    Normally, specific locations that run hot/burn/scorch happen because of bad/dirty/corroded/poor crimp/loose connections (or corroded wire).

    Replacing the connection with new metal (wire, connector, crimp, etc.) and clean the terminal assembly. And reattach.

    Given that there are two wires (+ and -)--And the other cable end did not fai(?), it appears to be limited to the Ve+ terminal. Again poor electrical connection (power = I^2 * R -- High resistance increases heat, 2x more current means 2^2 = 4x more heat).

    A sort of common issue with electrical wiring. Make sure you don't get water "flowing/following the wiring" into the terminal. I have had multiple homes were water came down the wiring and dripped right onto the breaker terminal--And after many years, the connections slowly failed (lights blinking when refrigerator starts, etc.).

    I have seen conduit bring water from other parts in the building (apartment complex where conduit looked like a leaking faucet flowing water). 

    Using Drip Loops (wiring to box, drops and rises, then goes back into box) and/or bring cable into an electrical box from the bottom, and not the sides or top of the connection space.

    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset