Short term low voltage shore power effects

Heading for the Bahamas in a few weeks. I've heard through the grapevine that one of the marinas we stay in is having some power issues due to getting hit by Hurricane Matthew. A review on Active captain said they were only getting 197 V at the pedestal.

My boat is 50A 125/250. No inverter. What are the risks to the boat if I use their power for a few days? I've heard it can be hard on AC compressors and other things.

My plan is to check the power when I get there and ask around the docks from the other boats to see if they are having problems before we plug in. I can always run the genset at the dock f it is really bad.

TIA.

Low voltage is kinda tough on motors, makes them run hot and might be hard to start. Dual voltage electronics that are connected to 250 should be ok. Electronics that run on the 120 side can usually go down to 90v, so they *should* be ok, but the current going in will be higher which could cause problems on a marginal supply circuit.

Would be good to monitor voltage for while once your loads are applied. Usually a little voltage drop happens between shore and the boat. At that low a voltage, you don't have much margin at all.

Ken

That's pretty low. I'd run my genset if it really was that low unless I had a boosting transformer.

You need to be able to check the voltage at the boat with your loads on to really know what's going on. You could see higher voltage at a power pedistal than you really have once you put a load on the line.

Loads like lights and ovens won't care about the low voltage much. But it can be very bad for things like aircon and refrigeration compressors.

Your air con motors will be labeled with the voltage limits.

OK, I can check it at the panel, I hadn't thought about that. Thanks for the advice.

I can also run my fridges on DC power, so they shouldn't be an issue.

Battery Charger? Would it be OK at low voltage?

Dougcole said:

OK, I can check it at the panel, I hadn't thought about that. Thanks for the advice.

I can also run my fridges on DC power, so they shouldn't be an issue.

Battery Charger? Would it be OK at low voltage?

Click to expand...

The battery charger specs should clearly list the voltage range it is capable of running on.
For example mine is rated for 90-135vac.


Ken

When hooking up to a potential low voltage source, start AC's first with other loads off and listen that the compressors start. If they just hum, turn off immediately. If they start ok, usually you are good to go. If you want to add resistive loads like water heater, do that with AC's off. Don't leave water heater on so it might energize at same time as ac's.

Batt chargers are usually not sensitive to input voltage, unless old ferro-resonant machines.

Do not let AC compressors hang in a stall condition!!!

Some of the newer battery chargers can take a wide range of input voltages.

This may be your answer. It describes how another Mainship 40 owner dealt with the issue:

208VAC MS400 Report.pdf

That's pretty awesome. Thanks so much for digging that up for me.

Just got back from a month long trip to the Bahamas. You will find quite a bit of problems from Hurricane Matthew at the marinas. Not only power problems, but internet problems as well.