RCD TRIPPING

[Alan de Enfield]

13 hours ago, SEPTEMBER MORN said:

What shore cable? I am connecting via the gen set

 

Your generator is on the shore* and down wind of the boat (isn't it ?) so the cable that runs from the boat to the generator is a 'shoreline'

 

 

* You don't run the genny on the boat do you ?

 

 

carbon-monoxide-safety-on-boats-final-dec2016.pdf

[SEPTEMBER MORN]

Hi Guy, thanks for all of your help, but I am getting confused here. 

 

I will wire the earth and neutral into the neutral position on the plug that goes into the generator - I understand this.

 

Now: Do I also wire the earth and neutral together at the end that I plug into the boat? (Where you would plug in the shoreline if hooked up whilst in the marina). 

 

Also: Do I, (or don't I), earth the genny to the boat via its floating earth?  If yes, then I will connect this earth wire to the earth stud on the hull that the inverters earth is fixed to

 

As I am a mechanical engineer and not an electrician, (but no a little bit about electricity), is it possible for yes / no answers only.

 

Again, thaks for all your help on this

[SEPTEMBER MORN]

2 hours ago, Alan de Enfield said:

Your generator is on the shore* and down wind of the boat (isn't it ?) so the cable that runs from the boat to the generator is a 'shoreline'

 

 

* You don't run the genny on the boat do you ?

 

 

carbon-monoxide-safety-on-boats-final-dec2016.pdf

Yes, but not in the boat, at the back of the boat - outside with the exhaust pointing away - hence me confused about the terminology.

[WotEver]

1 hour ago, SEPTEMBER MORN said:

I will wire the earth and neutral into the neutral position on the plug that goes into the generator - I understand this.

Great. 

1 hour ago, SEPTEMBER MORN said:

Do I also wire the earth and neutral together at the end that I plug into the boat?

No. No point as you’ve already done it at the other end of the cable as above. 

1 hour ago, SEPTEMBER MORN said:

Do I, (or don't I), earth the genny to the boat via its floating earth?

No. No point as it’s already achieved by answer 1. 

1 hour ago, SEPTEMBER MORN said:

... is it possible for yes / no answers only.

Yes

 

[Alan de Enfield]

8 minutes ago, SEPTEMBER MORN said:

Yes, but not in the boat, at the back of the boat - outside with the exhaust pointing away - hence me confused about the terminology.

That is far from ideal - you should be putting the genny on the bank, down wind of the boat - if it is on the back of the boat you can get Co and exhaust fumes dropping / blowing back into the cabin.

 

Petrol engines are notorious for producing CO.

 

Did you look at the Safety Link (from the BSS) I attached above ?

 

 

 

Little picture of a Genny on the back of the boat with a big-red-X thru it indicating 'don't-do-it'.

 

 

 

 

carbon-monoxide-safety-on-boats-final-dec2016.pdf

 

Whether the boat is moving or
moored, under certain running
and or wind conditions, CO at
dangerous levels can be
deflected or drawn in from
petrol engine exhausts.

Edited September 21, 2018 by Alan de Enfield

[Richard10002]

7 hours ago, blackrose said:

 

I'm not quite sure what you mean in your first sentence Richard? If you're bonding N-E on the cable then you should also be connecting the chassis of the generator to earth using the generator's earth stud. 

“I don’t think your genny earth should be connected to your boat Earth”

 

the picture created by the OP, (in my mind), was of a wire from the generator earth to the boat earth, (hull). I was merely suggesting that this wasn’t the way it is usually done.

 

Its my understanding that the genny earth stud is connected to the genny earth in the plug socket.

 

I agree that the N-E connection in the plug that goes into my generator connects the generator earth to the boat earth.

 

Let me stress that I’m no electrician, merely suggesting things that seem to have worked for me, having researched things.

Edited September 21, 2018 by Richard10002

[Steve42]

I suspect culprit is the generator. Inverter generators work by using high frequency pulse modulation, which is  stepped up in voltage and smoothed to remove, in theory all frequencies other than the 50Hz fundamental, however some harmonics will remain. The generator is at the cheaper end of the spectrum so I suspect more of these are getting through. There are various papers on the internet about how RCD's respond to these higher frequencies, some suggest they may trio at a lower current. The RF suppression in the inverter and maybe other equipment my also be passing some hf current to earth.

[WotEver]

2 hours ago, Steve42 said:

I suspect culprit is the generator. Inverter generators work by using high frequency pulse modulation, which is  stepped up in voltage and smoothed to remove, in theory all frequencies other than the 50Hz fundamental, however some harmonics will remain. The generator is at the cheaper end of the spectrum so I suspect more of these are getting through. There are various papers on the internet about how RCD's respond to these higher frequencies, some suggest they may trio at a lower current. The RF suppression in the inverter and maybe other equipment my also be passing some hf current to earth.

Quite possibly. Nevertheless he still needs to bond N-E. If the RCD continues to trip then he may need to change it. 

[WotEver]

13 hours ago, Steve42 said:

The RF suppression in the inverter and maybe other equipment my also be passing some hf current to earth.

Not without his N-E bond they can’t, because there is no path to earth. 

 

It’s all a bit odd...

[Chewbacka]

On 21/09/2018 at 10:26, SEPTEMBER MORN said:

Hi Guy, thanks for all of your help, but I am getting confused here. 

 

I will wire the earth and neutral into the neutral position on the plug that goes into the generator - I understand this.

 

Now: Do I also wire the earth and neutral together at the end that I plug into the boat? (Where you would plug in the shoreline if hooked up whilst in the marina). 

 

Also: Do I, (or don't I), earth the genny to the boat via its floating earth?  If yes, then I will connect this earth wire to the earth stud on the hull that the inverters earth is fixed to

 

As I am a mechanical engineer and not an electrician, (but no a little bit about electricity), is it possible for yes / no answers only.

 

Again, thaks for all your help on this

Just to clarify the gennie connecting cable should be wired up as a normal shore power lead AND with an extra short wire joining the neutral to earth at the plug that plugs into the  Generator.  This assumes that the generator is NOT centre tapped.

[WotEver]

4 hours ago, Chewbacka said:

Just to clarify the gennie connecting cable should be wired up as a normal shore power lead AND with an extra short wire joining the neutral to earth at the plug that plugs into the  Generator.  This assumes that the generator is NOT centre tapped.

Exactly so

[SEPTEMBER MORN]

Forgive me for my ignorance but now another question: How do I know if it is centre taped?

 

Besides, another contributor helping with my dilemma has stated that you wire the earth to the neutral, not linking them with a short wire.

 

[Richard10002]

3 hours ago, SEPTEMBER MORN said:

Forgive me for my ignorance but now another question: How do I know if it is centre taped?

 

Besides, another contributor helping with my dilemma has stated that you wire the earth to the neutral, not linking them with a short wire.

 

If that was me, I’ve wired the earth to the neutral, in the plug that goes into the genny, with a short wire. I think that’s the same as linked with a short wire?

[WotEver]

4 hours ago, SEPTEMBER MORN said:

How do I know if it is centre taped?

See post 19:

https://www.canalworld.net/forums/index.php?/topic/98264-rcd-tripping/&do=findComment&comment=2199944

4 hours ago, SEPTEMBER MORN said:

another contributor helping with my dilemma has stated that you wire the earth to the neutral, not linking them with a short wire.

Not sure that I’m understanding the difference here. 

[Chewbacka]

46 minutes ago, WotEver said:

See post 19:

https://www.canalworld.net/forums/index.php?/topic/98264-rcd-tripping/&do=findComment&comment=2199944

Not sure that I’m understanding the difference here. 

I have a feeling he has connected the earth wire and neutral wire to the neutral pin and left the earth pin unconnected.

[WotEver]

12 minutes ago, Chewbacka said:

I have a feeling he has connected the earth wire and neutral wire to the neutral pin and left the earth pin unconnected.

He shouldn’t do that

 

[cuthound]

13 hours ago, Richard10002 said:

If that was me, I’ve wired the earth to the neutral, in the plug that goes into the genny, with a short wire. I think that’s the same as linked with a short wire?

 

Whilst schematically connecting neutral and eath together on the neutral pin is the same as putting a link between the earth and neutral pins, it is wrong to do it.

 

The earth pin is always longer on UK plugs (13 amp and 16 amp "commando" plug), so that when the plug is removed from the socket, the earth is always disconnected last. This isn't necessarily the case if you connect both wires to the neutral pin.

[WotEver]

On 25/09/2018 at 10:54, cuthound said:

Whilst schematically connecting neutral and eath together on the neutral pin is the same as putting a link between the earth and neutral pins...

But it isn’t. It leaves the case of the inverter unconnected. 

[SEPTEMBER MORN]

Hi guys,

Found this info on-line

https://www.boatsafetyscheme.org/stay-safe/electrical-safety/generators-and-power-tools/

https://www.thefitoutpontoon.co.uk/electrics/earth-bonding/

[cuthound]

10 hours ago, WotEver said:

But it isn’t. It leaves the case of the inverter unconnected. 

 

Quite right, unless he also moves the case earth connection to the neutral.

[WotEver]

On 27/09/2018 at 08:53, SEPTEMBER MORN said:

Hi guys,

Found this info on-line

https://www.boatsafetyscheme.org/stay-safe/electrical-safety/generators-and-power-tools/

 

https://www.thefitoutpontoon.co.uk/electrics/earth-bonding/

 

Yes, and?