RCBO nuisance tripping - need new ideas on isolating the issue

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I hate replacing parts without knowing the cause in the hopes of finding and fixing the problem.

But I think at this point, replacing the RCBO on Shore-1 with a new one is worth the effort. We will also replace the other RCBO of similar vintage with a regular 2-pole breaker to see if the tripping when testing on Shore-2 is pushed back to the Blue Sea ELCI.

This will provide some comparisons that might prove useful.

However, this will do nothing to discover the source of the time-based tripping.
You may never discover the cause of the time based fault. It may be on shore nearby, or on yours or a nearby vessel. I have three channel recording meter to monitor voltage and amp draw anomalies, but haven’t used it for low level leakage like this. I have discovered anomalies in the incoming power though, as different businesses come online in the mornings and evenings.
 
Quick update for anyone interested:

I replaced the 22 year old Merlin-Gerin with a Schneider Electric Acti 9 iDPN Vigi.
Day 1 - RCBO did not trip
Day 2 - RCBO did not trip, but ELCI at shore power inlet DID trip @ 0953
Day 3 - RCBO did not trip
Day 4 - RCBO did not trip

With the 3 x MP-IIs inverters in parallel in pass-through mode, the leakage averages 18 mA, which is normal according to my VE engineer.

After conversing with an Aussie Marine Electrical engineer who claims that he has used the B-Stop on several boats, I have purchased one and will install next week. He wrote a white-paper enclosed here. I will report back with test results.
 

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I have a similar problem. I have a single
MultiPlus Compact
12 | 2000 | 80-30 230V
The 220V supply comes from a socket next to my house.
The supply trips the sockets in the house.
When I turn the Multiplus off (switch in the middle position) there is no tripping.

Have you tried turning off your multiplus and seeing if that stops the tripping? If you are plugged in why do you need it on once the batteries are charged.
Gilbert
 
Maybe another venue (i.e. a new marina) as an experiment would yield different results.
 
I'm not sure why you have an isolation transformer, an ELCI, and the RCBO. Are you sure you are tripping on ground fault and not overcurrent? I know my Blue Seas ELCI doesn't let me know why it tripped.
 
I have a similar problem. I have a single
MultiPlus Compact
12 | 2000 | 80-30 230V
The 220V supply comes from a socket next to my house.
The supply trips the sockets in the house.
When I turn the Multiplus off (switch in the middle position) there is no tripping.

Have you tried turning off your multiplus and seeing if that stops the tripping? If you are plugged in why do you need it on once the batteries are charged.
Gilbert
My set up is for my sailboat. I have continuous loads, such as refrigerators, freezers, Starlink, battery BMS, etc. I need to keep charging the batteries, else they would fully drain in about a 7-10 days.

When not on the boat, I use an V.E. IP43 25A charger to keep up with the loads.

When on the boat, I have multiple loads from the galley, lighting, Aircon systems for heating/cooling, etc.

I really want to find out why the RCBO is tripping only at specific times. We have eliminated (to our satisfaction) that the time-dependent tripping being inside the boat.

That leaves shore-based issues. Is this case, I need to make the boat less susceptible to crappy power from the grid.
 
On the boat side why would you not ground the neutral at the panel and leave it at that. Just have it in one place. I don't know if it has anything to do with your problem but that is how it is done on systems I am familiar with. Seems like more opportunity for mischief having it move around.

Sam the marine engineer says that the ground-neutral bonding is as follows:

Isolation transformer casing is grounded via the shore connection.
The ship's ground is isolated from the shore power connection.
Neutral ground connection is in the isolation transformer when shore power is connected.
When the ship is inverting neutral ground bonding is in the inverter.

AC ground and DC negative are bonded.
 
On the boat side why would you not ground the neutral at the panel and leave it at that. Just have it in one place. I don't know if it has anything to do with your problem but that is how it is done on systems I am familiar with. Seems like more opportunity for mischief having it move around.

Sam the marine engineer says that the ground-neutral bonding is as follows:

Isolation transformer casing is grounded via the shore connection.
The ship's ground is isolated from the shore power connection.
Neutral ground connection is in the isolation transformer when shore power is connected.
When the ship is inverting neutral ground bonding is in the inverter.

AC ground and DC negative are bonded.
Because it is supposed to be bonded at the source. The source changes, so it can't be bonded at the panel.
 
Maybe another venue (i.e. a new marina) as an experiment would yield different results.
I tried a different dock in the same marina, that has its power feed from a different transformer. The RCBO tripped there as well.

One of my neighbors a few boats over is a retired electrical power engineer. He says that the power to the marina is at the end of the utility line. Upstream is a large cement plant and an auto dismantling/recycling plant that creates a large amount of reactive power and the likelihood that one of both plants is turning on/turning off some appliances that is helping to create the crappy power.

He is convinced that the marina power is suspect regardless of which dock I am tied to. He says that the my boat is too sensitive due to the 3 MP-IIs inverters that increased the baseline current leakage to 17-18 mA.

AC power components (click here)

Look a few messages back and you will see the B-Stop device that I am going to try.
 
Because it is supposed to be bonded at the source. The source changes, so it can't be bonded at the panel.
Without transformers yes. With transformers no.

I have no experience stacking inverters but don't see how it can be any different. There can't be three different green grounds.
 

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Assume you would already have checked, but in VeConfig, do you have the Ground Relay flag ticked on all 3 Multipluss or just the Master?
 
@sparky #66
“ I know my Blue Seas ELCI doesn't let me know why it tripped."
Are you certain of this? AFAIK, all of the BS ELCIs will indicate if they tripped on leakage or on overcurrent.
 
90% of the time it involves old breakers and weak springs. Replace the breakers.
you could discuss it with boat on the same pedestal. See if they have similar problem
 
Update:
1. I replaced the 22 year old Merlin Gerin RCBO with a new Schneider RCBO. In four days, the new RCBO did not trip, but the Blue Sea ELCI tripped once on day two but not again.

2. I have installed the B-Stop.
I set the preset of device to null out 5mA of leakage current. No trips in the past two days.

Here are some pictures of my test results using a Hioki 3283 current leakage tester.

• No B-Stop, 0.42 mA, Shore power off, innverting mode
No B-Stop, 0.42 mA, Short power off, innverting mode


• B-Stop, 1.26 mA, Shore power on, inverters breakers off, in inverting mode
No B-Stop, 1.26 mA, Shore power on, inverters breakers off, in inverting mode


• No B-Stop, 5.51 mA, Shore power on, inverter power breakers on, in the inverting mode
No B-Stop, 5.51 mA, Shore power on, inverter power breakers on, in the inverting mode


• No B-Stop, 18.9 mA, Shore power on, inverters in pass-through mode, 251 V, 60 Hz
No B-Stop, 18.9 mA, Shore power on, inverters in pass-through mode, 251 V, 60 Hz


• B-Stop active, 4.28 mA, Shore power on, inverter breakers on, no pass through, inverting on
B-Stop on, 4.28 mA, shore power on, inverter breakers on, no pass through, inverting on


• B-Stop active, 5.71 mA, Shore power on, inverting, no inverting pass through
B-Stop on, 5.71 mA, Shore power on, inverting, no inverting pass through


• B-Stop active, first on the leakage starts at 9.68 mA, shore power on, inverter breakers on, inverter pass through on 251 V, 60 Hz
B-Stop on, 9.68 mA, shore power on, inverter breakers on, inverter pass through on 251 V, 60 Hz


• B-Stop active, settles at 12.3 mA in a few minutes, inverter pass through, MW on, IP43 Charger on

B-Stop active, 12.3 mA, inverter pass through, MW on, IP43 Charger on
 
@sparky #66
“ I know my Blue Seas ELCI doesn't let me know why it tripped."
Are you certain of this? AFAIK, all of the BS ELCIs will indicate if they tripped on leakage or on overcurrent.
100% positive of this. There is a label for ELCI LED, but the LED is not populated. I called Blue Seas on this, and they said the same faceplate is used for different models, and some have the indicator and some don't
 
Picture of the ELCI panel in my boat lazerette. (Only the power and AC main LEDs are on. The others are reflecting the flash.) I hope this helps.

All Photos - 1 of 1.jpeg
 
MeltimiCaz, Do you know if any of the other native "split-phase" 120V/240V boats at the marina - had GFPE tripping issues? Thanks.
 
Picture of the ELCI panel in my boat lazerette. (Only the power and AC main LEDs are on. The others are reflecting the flash.) I hope this helps.

View attachment 161026
Maybe not entirely relevant, but a couple observations:

1) your ELCI is 230V 32A and presumably intended for a 50Hz mains (UK/Europe?). I don’t think frequency should be relevant here, but as stated, just making observations. Also, if I’m not mistaken that is also 230V single phase, where in N.A. the 240V is split phase. Possible relevance?

2) attached is my ELCI, you can see all the LEDs lit as they are, and if there was a leakage trip that LED would indicate so.

IMG_5521.jpeg
 

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