Panel problems

[mcharles]

(NO PROBLEM) Correct voltage coming into top of main breaker, 220v. (PROBLEM) No 220v volt when measuring across buss bars or mounting bolts for breaker, only 110v from buss bars to neutral or ground.

 

[Reach4]

Try opening all of your 2-pole (240V) load breakers, and measure again. Keep the main breaker and the single pole breakers on during the measurement.

Also measure from each main breaker input to a bus bar. Normal would be near zero for the input to its associated bus bar, and it would be 240V to the other.

 

[Sponsor]

 

[Cwhyu2]

You have two sides to the buss bar, are you measuring buss to buss or one buss to neutral? If buss to buss should be 240 VAC, if one buss to neutral or ground should be 120 VAC.

 

[mcharles]

You have two sides to the buss bar, are you measuring buss to buss or one buss to neutral? If buss to buss should be 240 VAC, if one buss to neutral or ground should be 120 VAC.

Buss to buss, nothing. Buss to neutral 120v

 

[mcharles]

Try opening all of your 2-pole (240V) load breakers, and measure again. Keep the main breaker and the single pole breakers on during the measurement.

Also measure from each main breaker input to a bus bar. Normal would be near zero for the input to its associated bus bar, and it would be 240V to the other.

Will try, thank you

 

[Jadnashua]

Do you get 120vac from each bus to neutral separately? If so, you should have 240vac. The only way you might not actually have 240vac there is if somehow, they jumpered the same L1 or L2 to the other side, and did not connect the other corresponding L1 or L2 to the other bus (i.e., both busses have the same input - so, measuring between them would read zero - like measuring with both probes on the same point).

 

[Highlander]

Are you sure you're measuring across bus bars? It's a bit counter intuitive at first especially if the panel is full, but "phase" alternates going up/down between breaker positions, but positions directly across left-right are on same "phase". Here's the best picture I could find to illustrate that. The two red squares show where breakers would sit, those two connect to the same bus bar even though they are on opposite sides.

(Using the term "phase" loosely as it's actually single phase with a center tapped transfo)