Monitoring of onboard electrical system

[Portofino]

well I beg to differ...

it's v.helpful to be able to monitor how ONE device is doing...
FE, watermaker will suck 12A (geny is 8KW) when working properly prefilters clean, etc.
Will drop to 10A if I'm going too fast for it and cannot suck enough water to produce the expected 120lph of if prefilters are fouled slightly.
So just looking at it I know how this device is functioning
Similarly on the stabs if operating through the el.motor and not engine.

now sure I'd have any use for the PF that P. now also has though

cheers

V.

PS. haven't bothered turning on the AC this year, but that is a constant load nothing I've noticed changing on it

But exactly
“you soon know and adopt behaviour to accommodate what’s offered .”

Learnt to keep the WM in tip top condition and figured out it makes more water if you go slower .
And revising the pick up scoop , size shape , location or a combo of theses factors is on the list of to do jobs .....that never gets done ... keeps getting pushed to the bottom by more urgent things

 

[MapisM]

now answering your question why this huge fluctuation on the PF reading, I think its a combi of
1) many modern (lo Q) 230V adapters / switched power supply's have a bad PF
2) when AC consumption is very lo, your PF display is out of its usefull range, and does a wrong calculation, (like dividing by nearly zero ...)

Thanks B, makes sense. As well as your suggestion to not worry about PF, of course! :encouragement:

 

[MapisM]

P, are you saying that you trip your RCD if you're running too many power consuming items at once?

Actually, in a properly built shorepower supply, it's the circuit breaker rather than the RCD that is supposed to trip whenever the current absorption exceeds the rated capacity of the line.
The alternative would be wires overheating, melted insulation, and possibly a fire...! :ambivalence:

Anyway, yes, of course it's possible to trip the breaker (I guess also with your boat), depending on the available shorepower and the onboard equipment/appliances.
For instance, when all you've got is 16A, it doesn't take a lot of AC equipment to reach that limit.
My airco alone takes more than 16A, though I can (barely) run it with 16A, if I use just one of the two compressors.

PS: just in case this is what you meant, of course the problem is neither the onboard RCD nor the various onboard breakers.
They are designed to work with an 11kW genset, i.e. 50(ish) Amps.
It's the shore side of the electrical circuit, with its breakers, that is at risk when you pull from it more current than it's designed to supply.

 

[rlw]

Was considering fitting one of these myself. Looks rather well designed.

https://www.simarine.net/

 

[rubberduck]

On our previous boat the alarm system had such a facility, we simply set it to tell us if the current droped by a certain voltage, we set this to just bellow charging number so we knew when someone unplugged her & would phone marina to investigate.