Half of 120 volt buss is dead

[PmsPks]

I have lost the power to half of the 120 volt power buss. I have checked the main 50 amp breaker and it is good. Both L1 and L2 incoming are hot. Half the breakers are hot, the other half of the breakers are not. I can usually figure these things out, but this one has me baffled. Appreciate any ideas.

[RoyB]

Be sure to double check all of your GFCI breakers.. Do a reset on them...

[BB_TX]

You say you checked both L1 and L2 on the main 50 amp breaker and have 120 vac incoming on both. But did you check the load side of the main 50 amp breaker to make sure you have 120 vac coming out of the breaker to the distribution panel. Main breaker could have a bad leg.

[CA_Traveler]

Pull the 50A breaker and if all of the connections are clean and tight including to both of the busses then replace the breaker.

[PmsPks]

lanerd wrote:
I would first check the transfer switch output lugs to make sure you have 120 on both L1 and L2.

I have checked the voltage on both L1 and L2 wires coming into the 50 amp breakers and they are both 120v.

[PmsPks]

sch911 wrote:

PmsPks wrote:
Yes I have a generator. Wouldn't the transfer switch affect the entire 120 volt buss, not just half of it?

50A Service is two separate legs of 120V power, so you can loose one of them.

I understand that, but both legs coming into the two 50a breakers are hot.

[lanerd]

I would first check the transfer switch output lugs to make sure you have 120 on both L1 and L2.

[sch911]

PmsPks wrote:
Yes I have a generator. Wouldn't the transfer switch affect the entire 120 volt buss, not just half of it?

50A Service is two separate legs of 120V power, so you can loose one of them.

[PmsPks]

Yes I have a generator. Wouldn't the transfer switch affect the entire 120 volt buss, not just half of it?

[phays]

You could try swapping the incoming wires between the 50 amp breakers. Could be a faulty breaker.

[sch911]

Do you have a generator? If so check the transfer switch.