Fridge 12v relay ?

[Vicdicdoc]

I'm fitting a Dometic RM123 three way fridge, the 240v connection is straight forward as is the gas - the 12v had me stumped as it (as I understand) requires a relay (?) from the battery to the fridge, are all relays the same or do I require a certain type ?

 

[Wissel]

The relay should switch the fridge on when the van is running, so being charged from the alternator and is at a higher voltage. It's called a Voltage Sensing Relay or VSR.

A good choice is a Smartcom like this:

I see your in North Wales, anywhere near Colwyn Bay?

Reason I ask, is I have one here, new and unused, that you can have cheap. Plus I can talk you through the wiring if it helps.
David

 

[Vicdicdoc]

Hi David,
I’m located in Wrexham but a trip out in the car isn’t too far - what price are you asking?
Vic

 

[Vicdicdoc]

David, I already have a STERLING battery to battery unit fitted in my van, it’s the 12v fridge Relay I need - does your ‘smartcom’ do this ?
Vic

 

[Wissel]

David, I already have a STERLING battery to battery unit fitted in my van, it’s the 12v fridge Relay I need - does your ‘smartcom’ do this ?
Vic

Yep. Here's a drawing of my old elecs with the Smartcom where it would have been fitted (ended up with a compressor fridge):

The live from the Smartcom can be attached anywhere from the starter battery, to the connection on your Sterling. This will mean it only comes on when the stater battery is being charged.

Hi David,
I’m located in Wrexham but a trip out in the car isn’t too far - what price are you asking?
Vic

You can have it for a fiver. Let me double check it's where I remember though before travelling

 

[Vicdicdoc]

Ok sounds good

 

[Wissel]

Cool. I'll be in the workshop within the hour, so I'll let you know then if I found it. I'll PM you my details if so.

 

[Vicdicdoc]

Ok cheers

 

[Wissel]

Was where I thought it was

I'll PM you.

 

[Vicdicdoc]

Brilliant

 

[n brown]

smartcom is ideal for the job - good price too !

 

[Tommymanc]

Hi, does anyone know where I can buy the smartcom relay from?

Thanks
Tom

 

[mistericeman]

Hi, does anyone know where I can buy the smartcom relay from?

Thanks
Tom

Smartcom Voltage Sensing Split Charge Relay 12V / 30Amp

Split Charge Relay, Voltage Sensing Relay

brocott.co.uk

 

[SquirrellCook]

I know it's a touch more expensive, but this is a better option.

Orion-Tr Smart DC-DC Charger Non-Isolated - Victron Energy

The Orion-Tr Smart DC-DC charger is a professional DC to DC adaptive 3-stage charger with built-in Bluetooth. For use in dual battery systems in vehicles...

www.victronenergy.com

 

[Nabsim]

I know it's a touch more expensive, but this is a better option.

Orion-Tr Smart DC-DC Charger Non-Isolated - Victron Energy

The Orion-Tr Smart DC-DC charger is a professional DC to DC adaptive 3-stage charger with built-in Bluetooth. For use in dual battery systems in vehicles...

www.victronenergy.com

Wrong thread? This is for energising a 3 way fridge when driving?

 

[mistericeman]

I have to say....
I wouldn't EVER use one of those smartcom relays as a split charger...
I've fitted several in the past to landrovers etc (before the durite ones came out) and they all failed in short order....

Maybe OK as a fridge relay BUT definitely to be avoided as any means of split charging.

 

[wildebus]

Depending on how you want to enable them, for a 3-way Fridge running on 12V, a basic 30/40A 5-pin relay for a couple of quid is a good way to go if using a D+ signal to control - reasonably reliable and available from loads of places on-line as well as places like Halfords and other Motor Factors so dead easy to replace if need be.
Another popular way is using the TEC3M Relay that uses Voltage Sensing to switch on. Common for towing electrics and the switched 12V is the typical "Fridge" circuit in caravans and also used in Campers. Again very easy to find if replacement is needed.