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Topic: No power when plugged in (Read 2095 times) previous topic - next topic

No power when plugged in

Until recently i have my coach plugged into shore power and everything was fine.  Power showed in the power watch meter and everything charged etc as normal.
I took the coach out to put on the street unplugged everything and then ran the generator to test ac' s etc
Turned off the generator and then plugged it in again. I hear a click from the transfer box. nothing shows in the power watch meter
Is there a breaker or fuse i should be looking at resetting??
This is a first
Peter    Alberta Canada
'98 U320 40'  Build 5359 M11 450 HP, Aqua hot, Blu Ox

Re: No power when plugged in

Reply #1 –
With generator off, shore power disconnected, remove the cover for the ATS (Automatic Transfer Switch).

Check that all screws are tight and no wires burned.

Plug in to shore power.

Check for power IN and OUT
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: No power when plugged in

Reply #2 –
Is your shore power outlet 50 amp?

First place to look for trouble is Switching Relay #1 (see diagram linked below).  It is the one that selects between shore power and generator.  After sitting for a while in one position, it is possible for the contactors inside the box to get "sticky" and not reposition when power input is changed.

A little light mechanical persuasion with rubber mallet on the side of the ATS box might get things moving.  If you are comfortable with opening the box up when the power is "live" you can move the contactors with a non conducting tool, like a piece of wood dowel.

https://www.foreforums.com/index.php?media/item/a-2700-07-1995-u295-u320-110v-elect-relay-system-w.5206/
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Surely, no age has been more fraught with insecurity than our own present time."

Re: No power when plugged in

Reply #3 –
Perhaps voltage is under or over what the power monitor will let in. (if the 98 has the power monitor)
Dan - Full timing since 2009
2003 U320 40' Tag 2 slide

Re: No power when plugged in

Reply #4 –
How to check a typical ATS:

https://www.youtube.com/watch?v=TpPkj8aTcyE
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Surely, no age has been more fraught with insecurity than our own present time."

Re: No power when plugged in

Reply #5 –
Quote from: AC7880 –
Perhaps voltage is under or over what the power monitor will let in. (if the 98 has the power monitor)

Great point!  If there's a built-in Progressive EMS, that would prevent low or high voltage from passing.

('98 wouldn't have had the Maverick transfer switch with the over/under relays.  That didn't show up until after 2000.)
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: No power when plugged in

Reply #6 –
No Shore Power / ATS issue? 
Dan - Full timing since 2009
2003 U320 40' Tag 2 slide
 

Re: No power when plugged in

Reply #7 –
Thanks for the response
After checking my EMSLCHW50 it was evident. It said E 1 reverse polarity. So i got out my portable power watchdog to confirm and sure enough it was a bad extension cord. After replacing everything was normal!!
Peter    Alberta Canada
'98 U320 40'  Build 5359 M11 450 HP, Aqua hot, Blu Ox