Electrical Projecta VSR 100 for controlling caravan power supply from Pajero?

[speedygp]

Gooday all,
I`ve installed a dual battery system on our NT Paj (Projecta 150 kit)with a yellow top AGM as the extra batter. I`ve had this system working well for a while now and decided to add a feed to the rear of paj and Anderson plug to connect Expanda Dometic 2350 fridge for 12 volt operation whilst driving.
After reading various forum posts I purchased and installed a Projecta VSR 100 immediately off the 2nd battery.
The idea was that I could connect van fridge to Paj, and whilst the Paj was running and charging above the lower threshold of 12.8v, it would run the fridge, but once stopped, no 12 v to relay would disengage solenoid and prevent battery discharge and flattening.
I connected everything up as per instructions, but without the manual override, as I believed I wouldn`t need it for this application.I added one of those cute little Anderson covers with an LED to show power.
Turned on- no power to rear
No LED illumination
No LED illumination on relay
14.2v on supply side of relay- nothing out
Thinking the relay may be a bit tight or stick? I connected the manual override up as per instructions, switch LED illuminated OK but still no voltage downstream.
Next step was to jump across the main terminals, 14 volts at Anderson plug at the rear.
Just in case of wrong assembly I tried connecting the override lead to the other terminal of the VSR block, no change.
I contacted the supplier who was helpful, but said that the Projecta VSR wouldn`t do what I wanted, and I needed a continuously rated solenoid to do what I wanted.
The Dometic fridge specs show it draws 175 watts.
Can I do what I want to with what I have, is the Projecta not functioning, or have I just got hold of the wrong gear to do the job?
I`d value suggestions from anyone who has succeeded or failed with what I`m trying to do, I`m not a techno, but reasonable with a multimeter.
The only thing I can think of I may have done wrong is connecting 12v control wire to battery, and not to ignition, so may not be triggering cut in/out?

 

[Base23]

I use a Narva 61092BL VSR on my set up to supply power to my van fridge whist traveling and it works fine. Although with new vehicles the alternators they run are variable voltage units so some times even when the engine is running it still may not be producing over the 13.3 volts I need for my VSR to cut in.

If you are getting 14v at the input terminal of your VSR it should be automatically turning on so it sounds like you have a faulty projecta unit.

Projecta do a unit called a low voltage disconnect that is more suited to what we are trying to do and I will fit one of them next time.

Cheers

 

[boots33]

Some VSR's designed for dual battery operation require a battery on both sides of the heavy terminals before they will connect. From reading the installation manual it would appear that is not the case with the vsr100 so it should be ok for what you are trying to do, provided you have it hooked up as the manual describes

MAIN to your battery
AUX to your anderson
Make sure the unit has a good earth

The manual switch will work as long as you have it connected to + 12v It does not need to be an ignition circuit although that is the most common way when used for dual batteries. If you are getting 14v that is well over the 13.4v needed to activate the relay and as long as you are getting more than 10v the manual switch should make it connect.

You have already tried connecting your 12v across the main and aux terminal so that would have made it connect if it needed battery on both sides.

It does look as though you have a faulty unit. If you have an auto sparky nearby they would be able to test the unit very quickly and I doubt they would even bother to charge for the service.

 

[speedygp]

Sorry, been busy for a couple of days. I spoke to the auto elec at work who convinced me that my setup with the Projecta VSR should work. Went home that night and realised why it wasn`t working- I hadn`t earthed the control side of the solenoid, only the override switch. Once i earthed it out the relay pulled in and the LED lit up! woohoo
Thanks for the help!

 

[boots33]

Great to hear. Make sure you have a 20A fuse fitted in the fridge wiring as well.

 

[speedygp]

Great to hear. Make sure you have a 20A fuse fitted in the fridge wiring as well.

Thanks Boots, picked one up this arvo. Attached is a pic of the nearly finished job, I made a cover for the negative terminal out of the pivot cover of the 3rd row seats recently removed.
Great forum, cant beat the collective intelligence here, especially if you steer clear of touchy subjects like ATF, or engine oil!!!

Thanks again all!