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Half of 120 volt buss is dead

PmsPks
Explorer
Explorer
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.
Paul & Pam
2007 Damon Tuscany 4076
2007 Jeep Wrangler
24 REPLIES 24

RoyB
Explorer II
Explorer II
Be sure to double check all of your GFCI breakers.. Do a reset on them...
My Posts are IMHO based on my experiences - Words in CAPS does not mean I am shouting
Roy - Carolyn
RETIRED DOAF/DON/DOD/CONTR RADIO TECH (42yrs)
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2010 F150, 5.4,3:73 Gears,SCab
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BB_TX
Nomad
Nomad
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
Explorer III
Explorer III
Pull the 50A breaker and if all of the connections are clean and tight including to both of the busses then replace the breaker.
2009 Holiday Rambler 42' Scepter with ISL 400 Cummins
750 Watts Solar Morningstar MPPT 60 Controller
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Bob

PmsPks
Explorer
Explorer
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.
Paul & Pam
2007 Damon Tuscany 4076
2007 Jeep Wrangler

PmsPks
Explorer
Explorer
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.
Paul & Pam
2007 Damon Tuscany 4076
2007 Jeep Wrangler

lanerd
Explorer II
Explorer II
I would first check the transfer switch output lugs to make sure you have 120 on both L1 and L2.
Ron & Sandie
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sch911
Explorer
Explorer
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.
OEM Auto Engineer- Embedded Software Team
09 Holiday Rambler Endeavor 41SKQ Cummins ISL
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PmsPks
Explorer
Explorer
Yes I have a generator. Wouldn't the transfer switch affect the entire 120 volt buss, not just half of it?
Paul & Pam
2007 Damon Tuscany 4076
2007 Jeep Wrangler

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

sch911
Explorer
Explorer
Do you have a generator? If so check the transfer switch.
OEM Auto Engineer- Embedded Software Team
09 Holiday Rambler Endeavor 41SKQ Cummins ISL
2012 Jeep Grand Cherokee Limited Toad