Where are the shore power voltage regulators?

[Corvidae]

So it's summer here in Florida, which means the power grid is doing it's happy dance of failure, especially at the marina. The place where it's crazy hot and everyone is running their most power hungry messed up air conditioner to try and survive the burning inferno.

Which is why my shore power is very often lacking in 'power'. Often fluctuating from 250 to 160 volts. Which is really starting to piss off my poor inverter/charger every time the voltage drops it bounces the whole system to keep from drawing crazy amps for my own air conditioner.

Which leads me to my question. In the RV world they have these:
https://smile.amazon.com/dp/B01MXL9YJV
And others like them. So why can't I find these for a boat? I can attest from experience that marina power is just as horrible as any RV park, and we're running all the same systems, just with more corrosion.

[ttex]

What you are describing sounds bizarre.

Are you getting 240 from shore? Or 120?

[Corvidae]

It's a standard 120/240 50 amp shore power connection. Actually using a y connector right now to combine the two 30amp connections into one 240v 50amp. The voltage fluctuations are various boats drawing too much before the power recovers. Usually very brief fractions of a second for the big drops. Most of the time it's slow ranging from about 251 down to 243.

[Jammer]

Well, the autoformer-type systems have bells and whistles and LEDs that convince people who buy them that they got their money's worth


But in most cases they don't solve any problem that anyone actually has. They operate within a narrow range and will drop the shore power connection if it goes to 160 volts, in fact, most drop it at around 200 or 210 volts.


Most air conditioners will work OK on 200 or 210 volts so the autoformer type devices don't help much.


Some of the better inverter/chargers will provide load support and can be set to draw no more than a certain number of amps from the shore power input then they will invert to make up the additional amps required. Then when there are extra amps they'll switch to charging mode. A side effect of this is that some of these designs can transfer the load instantaneously if the shore power goes out of spec. I believe the Victron plants are set up this way. Something to consider

[Shrew]

Originally Posted by Corvidae

Often fluctuating from 250 to 160 volts. Which is really starting to piss off my poor inverter/charger every time the voltage drops it bounces the whole system to keep from drawing crazy amps for my own air conditioner.

I'm not clear on this statement. Are you running the Air Conditioning through the inverter?

[AKA-None]

Well that sounds like a marina issue unless you have a really crappy grid there. If the grid bounced like that it would go offline

[Corvidae]

Yes my main ac is on pass through on the 10kw inverter/charger, usually carrying about 3 to 5kw. Works fine most of the year, not so much for the past month as it's gotten really hot outside.

[ttex]

Im going take a wild guess and say one of your two shore power cables is compromised. I damn near guarantee it.

[ttex]

If a wire or connection is loose or damaged you can test it with a meter and get 240 but when put under load you wont actually get 240.

Im pretty dang positive this is your issue.

[Corvidae]

I suspected the same, so I plugged into a pedestal across the dock from me with my sander. Which gave me random RPM's as the voltage floated around. I'd say that was definitive, but that sander also just ate itself in horrible ways this morning. So I'll be doing some more troubleshooting on that.

[RaymondR]

The marina AC network is probably not designed to support all those air conditioners.

[Corvidae]

Originally Posted by ttex

If a wire or connection is loose or damaged you can test it with a meter and get 240 but when put under load you wont actually get 240.

Im pretty dang positive this is your issue.

It stay's 240 or so with my loads for hours on end. Usually early in the day, and again towards the evening things get bouncy. Ac's turning on and boats coming in. At least that's my assumption. Mainly because I can run everything just fine for hours and hours with no problems, no hot wires etc.

[ttex]

If you draw too many amps it pops the breaker. It doesnt lower the voltage.

The voltage going crazy is a wiring issue.

Entirely possible the load center for your dock has a bad wire or connection somewhere.

[RaymondR]

Originally Posted by ttex

If you draw too many amps it pops the breaker. It doesnt lower the voltage.

The voltage going crazy is a wiring issue.

Entirely possible the load center for your dock has a bad wire or connection somewhere.

Maybe, but some of the marinas I have been in have long cable runs between the breakers, which are usually installed on the land side at the ramp down to the floating pontoons, and boats at the outer ends of the fingers.

[YANDINA]

Why can't you use that one? It appears to be marine quality.