Replacing diesel genny with inverter

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Travelling Westerly

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Ive removed an old diesel powered generator that was more trouble than it was worth.

Im left with a 3 way 240v selector switch on my control panel that says shore, off and generator.

My question is can I wire my 2000w inverter output into the generator side of this 240v selector switch? The intention is to be able to run my 240v ring main from my house bank.

Should the Victron Inverter also be earthed down?

Thanks in advance
 
Mark26 said:
I wouldn’t have thought there is any need to wire the inverter through the switch.
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(y)
True. But you will want a switch somewhere to turn the inverter off. A 2KW inverter will consume noticeable amount of current even if there is no load.

Does the inverter have a separate earth? I would have thought internally it would connect the earth on the output to the negative battery terminal. But I have never actually checked.
 
Heavens above, another lethal inverter thread!

If wishing to connect the inverter to the boats systems it must be connected via a changeover switch, the old genny switch is perfect for that. The switch must be a 2 pole one, which it's almost certain to be if it was used for a generator.

The Earth and neutral must be bonded at the inverter. If it's a Victron one it likely will be, what model is it ?

You must also connect the inverter Earth to the water. This can be a ground plate, a metal hull or an anode.

Note, most boats don't have a "ring main", more usual to have radial circuits. Also note, you'll want to avoid having heavy loads like an immersion heater running from the inverter and you also want to avoid having a mains battery charger connected to it.**

**Don't have the mains charger turned on when using the inverter, if it's connected to the 240V outlets.
 
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westernman said:
(y)
True. But you will want a switch somewhere to turn the inverter off. A 2KW inverter will consume noticeable amount of current even if there is no load.
Click to expand...

Not true, it must be connected via a changeover switch. That's not to be confused with an off switch. The changeover switch stops you from having shore power and the inverter connected at the same time, which will result in a very unpleasant bang. The inverter off switch is to turn the inverter off (surprise surprise :)) to save the standby current that you mention, usually between 0.5 and 1.0A, depending on the inverter.

Does the inverter have a separate earth? I would have thought internally it would connect the earth on the output to the negative battery terminal. But I have never actually checked.
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The inverter should be be connected to the water, as in "Earthed". It will not have an internal connection between the AC out Earth and the DC negative, it should have a connection between the Earth and neutral. If it's a type of inverter that cannot have that connection, it's not suitable for the OPs purpose. This connection is possible in the OPs case, as he has a Victron inverter.
 
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PaulRainbow said:
Heavens above, another lethal inverter thread!

If wishing to connect the inverter to the boats systems it must be connected via a changeover switch, the old genny switch is perfect for that. The switch must be a 2 pole one, which it's almost certain to be if it was used for a generator.

The Earth and neutral must be bonded at the inverter. If it's a Victron one it likely will be, what model is it ?

You must also connect the inverter Earth to the water. This can be a ground plate, a metal hull or an anode.

Note, most boats don't have a "ring main", more usual to have radial circuits. Also note, you'll want to avoid having heavy loads like an immersion heater running from the inverter and you also want to avoid having a mains battery charger connected to it.
Click to expand...
I stand corrected.
Thank you Paul.
I don’t have one, but I was under the impression that they had a feed from the battery like any other appliance, and then had a mains outlet.
 
Phew, thanks Paul, I was wondering if I worded the post wrongly and confused everybody.
As usual Paul to the rescue (y)

OK the Victron is a 2000w Phoenix pure sine wave smart. I have a grounding plate that I can use to earth it but I'm currently using that for my navigation equipment RF drain/noise. Would sharing that with the inverter earth cause any backfeed issues/damage the Raymarine gear?

The selector switch is a 2 pole as you say. I also thought it was perfect for powering up the radial circuit but wanted to check with you first.

I could use an anode to earth it down if you think sharing the ground plate with my RF drains will be an issue.
I take galvanic corrosion won't be an issue as I'm obviously not connected to shore power when the inverter is in use?

Out of interest why not have a mains charger connected to the inverter supply battery?
It currently has sterling Pro 30A charging it off shore power but that would be off when using the inverter.

Cheers
 
Cornishwesterly said:
OK the Victron is a 2000w Phoenix pure sine wave smart. I have a grounding plate that I can use to earth it but I'm currently using that for my navigation equipment RF drain/noise. Would sharing that with the inverter earth cause any backfeed issues/damage the Raymarine gear?

The selector switch is a 2 pole as you say. I also thought it was perfect for powering up the radial circuit but wanted to check with you first.

I could use an anode to earth it down if you think sharing the ground plate with my RF drains will be an issue.
I take galvanic corrosion won't be an issue as I'm obviously not connected to shore power when the inverter is in use?

Out of interest why not have a mains charger connected to the inverter supply battery?
It currently has sterling Pro 30A charging it off shore power but that would be off when using the inverter.

Cheers
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Nice inverter. No problem sharing the ground plane. The case of the inverter has to be Earthed. Making the Earth connection will mean the shore power Earth will also be connected to the water, so you would be advised to fit a GI.

Ref the battery charger, i was probably not clear. What i meant was, make sure the charger is turned off when using the inverter, if it's connected to the 240V sockets. You don't want to be charging the batteries with the inverter, which is powered by the batteries :)
 
Thanks for the reply Paul

Got you ref the mains charger (y)

Currently the mains earth circuit is isolated on the boat so earthing down the inverter casing will change that position. Other than using my GI, is there anything else I should consider with earthing? Is that going to cause any issues with other circuits that are not earthed?

Appreciate your help now and in the past. Thinking about putting a plate in my electronics bay stating "designed in conjunction with PR" :D
 
I think you will find something like a Victron Multiplus which functions both as a charger and as an inverter has two different earths which need to go to different places.

It is important to get the earthing right, or your anodes (or your boat if it is aluminium) will disappear at lightning speed.
 
Cornishwesterly said:
Thanks for the reply Paul

Got you ref the mains charger (y)

Currently the mains earth circuit is isolated on the boat so earthing down the inverter casing will change that position. Other than using my GI, is there anything else I should consider with earthing? Is that going to cause any issues with other circuits that are not earthed?

Appreciate your help now and in the past. Thinking about putting a plate in my electronics bay stating "designed in conjunction with PR" :D
Click to expand...

I would fit a GI on the incoming shore power Earth, connect the boat side of the GI to the main Earth busbar. Also connect the case of the inverter to the Earth busbar. All other onboard Earth connections should be made here too (already?). You then run a single wire from the busbar to the grounding plate, the current rating of the Earth cables must be at least that of the shore power or inverter rating.
 
westernman said:
I think you will find something like a Victron Multiplus which functions both as a charger and as an inverter has two different earths which need to go to different places.
Click to expand...

This is incorrect. There should only be a single Earthing point on a boat.

It is important to get the earthing right, or your anodes (or your boat if it is aluminium) will disappear at lightning speed.
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It is indeed important to get the Earthing connections right, least not because the 240V power, whether it be from shore power or from the inverter can kill.

Correct Earthing circuits do not influence galvanic corrosion one way or another, to prevent galvanic corrosion a GI or IT needs to be fitted, even if the Earthing is all spot on.
 
PaulRainbow said:
I would fit a GI on the incoming shore power Earth, connect the boat side of the GI to the main Earth busbar. Also connect the case of the inverter to the Earth busbar. All other onboard Earth connections should be made here too (already?). You then run a single wire from the busbar to the grounding plate, the current rating of the Earth cables must be at least that of the shore power or inverter rating.
Click to expand...
Thanks Paul
My GI is an inline version that plugs in between the shore power cable and the boats external shore connector. I have not bothered using it on this boat due to the following:
The 240v circuit earth's have no continuity with anything on the boat side. Earth's are led back to shoreside supply only.
The anode is connected to my rudder post, drive shaft (prop side only) and P bracket oh and stainless fuel tank. The shaft/gearbox coupling is isolated.
 
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