Low AC message.

[Steve1.0]

A Riviera 445 I manage has started showing a "low ac" message on the salon air conditioning (marine aire) unit's control. C-zone shows 1 leg of 220v 50A coming down to 108vac. Shore power cord tests at 118vac both legs.
While on ships power no error message. What am I missing, where to start looking??

 

[Bacchus]

Start backtracking the shore inlet from A/C input & AC power panel back to the shore cord / boat inlet. Where do you have 118V vs 108V?

Is the main power panel L1 & L2 at 118V or 108V
Connections at breaker?
Do you have an isolation transformer?
Boat side of the inlet connector?
Breakers at inlet connections?

Gen will by pass all of that and feed direct to the power panel buss so it must be in the shore path ahead of the power panel.

 

[CharlieJ]

Is the marina wired as a 208VAC split phase or 240VAC split phase. In Florida, in a 208 VAC marina, when all the boats upstream have their air conditioning operating the poor guy at the end of the pier is lucky to get >200VAC!

If this is your case, and if you do not want to install a boosting isolation transformer, a buck/boost transformer between the shore pedestal and boat inlet will correct this issue.