One side no power

[raymonyng]

Hi, I am a new guy. My eros2 after I welding and found out B side no power, A side have power, but the led didn’t light, the D1 l check there’s no voltage, and D6 have 247V, what can I do, please help.

[Paul Birkeland]

What are the IA, IB, OA, OB, KregA, and KregB voltages on the board above the D socket?

What are the voltages at IA, IB, OA, OB, OC, OD, OKA, OKB, OKC, and OKD on the forward board?

[raymonyng]

Hi, thanks for help,

     IA.   346V
     IB.    347V
     OA.   345V
     OB.       0V
     OKA.   30V
     OKB.     0V

      IA.       0V
      IB.    329V
      OA.       0V
      OB.       0V
      OC.       0V
      OD.       0V
     OKA.      0V
     OKB.      0V
     OKC.      0V
     OKD.      0V

[Paul Birkeland]

There's no OKA and OKB on the board above the D socket. 

[raymonyng]

Terminal check only the left output head is 46K not the 470K, see what’s wrong. Thanks.
Sorry, about the D Socket  that’s Kreg A and Kreg B,  not the OKA and OKB. you are right.

[Paul Birkeland]

Swapping those resistors won't cause the voltages to drop.  Remove the wires from IA and IB on the front board and let them poke up into the air, then recheck the voltages on the board above the D socket.

[raymonyng]

I disconnect the IB from IA then the voltage are:

     IA.        332V
     IB.            0V
     OA.           0V
     OB.           0V
     Kreg A.    29V
     Kreg B.      0V

[Paul Birkeland]

IA and IB are connected with a piece of wire.  Since your IA and IB are not the same, that wire is missing or broken.

The 29V at KregA will happen if one of the little resistors that goes to pins 2/7 on the D socket isn't well connected, or it's also possible one of the black wires back there is loose.