98 330 DA with 2 30 amp inlets....

[rsg]

98 330 DA with 2 30 amp inlets. I run a single cord to side of boat and then splitter into 2 inlets. Bottom or secondary line which powers air/heat and micro outlet  is fine. Top line or main is indicating reverse polarity thus nothing working i.e. ac converter, fridge, outlets ect... 

Any help on why top inlet would be bad but bottom is ok?

[wingless]

What happens when the boat is powered w/ two 120V, 30A power cords?

Is the boat being powered by a single 120V / 240V, 50A cord and a 50A plug to two 30A receptacle adapter, like a Marinco 153AY, or is the boat being powered by a single 120V, 30A cord and a 30A plug to two 30A receptacle adapter, like a Marinco 157AY?

[rsg]

Single 120v 30amp cord and then splitter to the 2 boat 30 amp inlets. I have tried different dock boxes and cords woth no spltter and have concluded it's somewhere inside the boat begining at the 2 male 30 amp inlets mounted on the side of the boat but where?

[wingless]

Thanks for the additional info.

A properly qualified person could measure the 120VAC voltages from the AC inlet to the salon distribution panel.

https://upload.wikimedia.org/wikipedia/commons/0/0d/NEMA_simplified_pins.svg

A properly wired receptacle will have 120VAC (nominal) from hot/line to both neutral and to ground.

It is likely that the factory used black insulation for the hot/line conductor, white for the neutral and green / yellow for the ground.

[wingless]

Another possibility is damage or degradation to the wiring and connectors from the improper usage of a 30A splitter to twin 30A connectors.

It is VERY easy to overload the components in that configuration by pulling waaay too much current through the system.

Part of the solution should be to retire that NEMA L5-30P to twin NEMA L5-30R splitter.

It should be replaced w/ twin 120VAC 30A power cords or a single 120VAC/240VAC 50A power cord w/ a NEMA SS2-50 plug to twin NEMA L5-30 receptacles.

Part of the investigation should include investigation for damage from operation in this method.

[rsg]

As always thanks for the discussion electrician is comming out this weekend to try and solve? Just wondered if it might be a bad outlet or something like that as I was thinking all 110 outlets and accesories i.e. oulets, ac converter, head system, fridge, water pump are tied together? Are some like ac cabin lights lights direct to ac 110 and others pull from battery i.e water pump

[wingless]

YW

The factory uses DC lights, powered by the battery. Also battery powered is the head and water pump. The 'fridge is dual power, for both AC and DC. The AC converter (battery charger), AC receptacles and air conditioner(s) are AC powered only.

[rsg]

As I thought the ac converter is just a fancy way to say battery charger. I will report back if electrician can resolve, hoping it's just a bad inlet or run to the panel.

[Mystique]

I had the same problem on my DA38 and it turned out to be a faulty 50amp breaker. Replaced it and all is good.

[rsg]

Mystery reverse polarity issue solved neutral wire was scorched and corroded on conection to the Inlet so it was throwing power back on the ground wire. Changed the inlet and cut the wire back about an inch for fresh new leads. All power restored to main breaker on the distribution panel. Im going to replace the secoundary line inlet as well for prevention. I am told over the years they corrode and get damaged. Most of the marinas would not give me the time of day when I tried to get service help. Luckily I found a great boat electrician who stopped by and probed the lead wires and immediately found the drop in voltage.

[wingless]

Good news.

It was mentioned that the wires feeding the inlet were corroded, but note that if the inlet blades are corroded, then it is likely that the connecting cord also has corrosion on those receptacle connections.