Need help with AC/DC Fridge switch installation

[Mark]

Hello,

We have a 27ft SCR 1991 Maxum and the fridge will only work on AC I had an electrician check it out and the DC circuit is not working

I have purchased a 1500 Watt inverter. I want to have a switch that allows me to either run the fridge from the shore power side or the inverter, but not both at the same time.

Below is a photo of the switch that I have purchased and plan on using for this job, I need your advice as to what I am doing is correct and will work.

See the images



This switch is rated at 15Amp 125 to 244V AC so it should be more than enough.

This is a switch that has two circuits either ON-OFF-ON

If you refer to the wiring diagram for the switch, my thought is to somewhat reverse the intention of the switch.

I plan to have the hot and neutral wire FROM the fridge connect to the POWERSOURCE on the switch. On the the one load side (say LOAD 1) I would hook up the hot and neutral from the shore power and on the other load side (say LOAD 2) I would hook it up to the hot and neutral from my 1500 watt inverter. This configuration would allow only the shore power or the inverter to power the fridge, but not both.

Do you think this is correct and do you think it will work fine?

Can I also marrette all 3 black wires together?

Also, rather than wrapping the stranded wired on the screws, I was planning on using a wire connector with a loop at the end and put that loop under the screws for each of the 6 wires

Thank you for your help
Mark

PS: Our boat is being launched this Sunday, Mother's Day, can't wait!

[irishladdie]

Mark,
The way you have mentioned to conect up the fridge will work ok, but do not put all the blacks together. Also you can buy conecters that look like a fork, they just slide under the screws instead of having to remove the screw, much easier.

[Gazjen]

It will work, but I would put the black wires to the switch the same as the live wires, as it could cause problems with an RCD in the shore power if you link them together

Also does that mean that the inverter will be on all the time as your going to be switching the 110-240v side? Because it will use power even in Idle from the 12V batteries

Another option that I'm sure you can get in the states is a 3000w inverter that has a shore power feed from the rear if your on shore power it automatically switches off the inverter. If shore power is lost the inverter cuts in so no loss in power. one of the models can even make up current by using the inverter if the shore power is say limited to 3 amp and you want 5

Bit more costly I know, but completely automatic

Just remember though on a inverter the fridge will use a lot more power than it did on its own DC circuit

[Mark]

Originally Posted by irishladdie

Mark,
The way you have mentioned to conect up the fridge will work ok, but do not put all the blacks together. Also you can buy conecters that look like a fork, they just slide under the screws instead of having to remove the screw, much easier.

Hi Irishladdie,
Thanks for the tip on the connectors, I will use the fork rather than loop type.

All the best with your new boat!

Thank you,
Mark

[Mark]

Originally Posted by Gazjen

It will work, but I would put the black wires to the switch the same as the live wires, as it could cause problems with an RCD in the shore power if you link them together

Also does that mean that the inverter will be on all the time as your going to be switching the 110-240v side? Because it will use power even in Idle from the 12V batteries

Another option that I'm sure you can get in the states is a 3000w inverter that has a shore power feed from the rear if your on shore power it automatically switches off the inverter. If shore power is lost the inverter cuts in so no loss in power. one of the models can even make up current by using the inverter if the shore power is say limited to 3 amp and you want 5

Bit more costly I know, but completely automatic

Just remember though on a inverter the fridge will use a lot more power than it did on its own DC circuit

Please let me clarify what I mean, sorry for confusion, there are three wires that are common to 120 volt 14/2 wiring,
Neutral (with white insulation covering)
Hot (with black insulation covering)
ground (bare wire with no covering)

The Neutral and Hot wires from shore will be on one end of the switch and the Neutral and Hot wire from the inverter will be on the other side of the switch and the Neutral and Hot wires from the fridge in the middle. All the Hot wires will be on the same side of the switch and all the Neutral wires will be on the other side of the switch.

So when I said "Can I also marrette all 3 black wires together?" I meant to say, can I marette the three ground bare wires together? So do you think this is ok?

Hmmmm, your comment on this fancy inverter this is food for thought, I may look for that inverter with an auto switch, nice function, as you say, nothing to worry about. Unfortunately, I bought the current inverter last fall on sale, probably cannot return.

Thank you,
Mark :mrgreen:

[Gazjen]

Ah I see, Yea putting all the ground wires together is fine

You do use some strange wire colour combinations over there

[Mark]

Originally Posted by Gazjen

Ah I see, Yea putting all the ground wires together is fine

You do use some strange wire colour combinations over there

Hi Gaz,

OK, thanks, I hope you are right, if not I will send you photos of our charred boat after the fire! ops:

Regarding the strange wire colour's, I thought that all house wire in North America would have been the same, what colours are your ordinary 14/2 household wiring in the US? Our's is black, white and bare copper for ground wrapped in a white plastic outer coating. If it's outdoor wire, it's black plastic outer coating.

Was at the boat today, so nice and quiet, too cold for most, but it was beautiful in the sunshine, can't wait for nice weather up her on the northern shores of Lake Ontario.

Thanks again,
Mark :mrgreen:

[Gazjen]

I'm in the UK we has just standardised our colours with Europe

Single Phase

Brown = Live
Blue = Neutral
Green and Yellow = Earth

Three Phase

Grey
Brown
Black
For the three positive phases

(Used to be Red, Yellow and Blue. Much easier to see in a darkened panel)

and Blue for Neutral

See how they has swapped a phase colour for a neutral colour in the new system! Clever Eh?

Green and yellow for earth

Anyway good luck with the fridge are you going to leave the inverter switched on all the time then at 12V?

[Mark]

Originally Posted by Gazjen

... Anyway good luck with the fridge are you going to leave the inverter switched on all the time then at 12V?

Sorry Gaz,

Thought you were in the US, that's quite the colour spectrum for wires in the UK :mrgreen:

I will use the inverter when we are on the water and shore power when we are connected at the dock, that's the purpose of the switch, hope this works!

Thanks again,
Mark irate: