Right. The bling has provision for a second battery in the boot. In its former life as a first response vehicle and gp lugabout the back seat was taken up by a computer and telemetry uplink. Defib. ECG and nebuliser machine. All this coupled with the flashing lights and radios used to eat the battery. So a second one was installed in the boot.
This got me thinking. I like to do the camping thing and i use a lot of 12v crap when i go camping. So how do i wire up a second battery to charge up but not sap charge from the main battery when being used to power things? Anyone got any thoughts. The bling takes its power by way of a little black box but the box has no markings.
second battery
As I understand it there are 2 systems used - one is a simple blocking diode - which allows the second battery to charge but does not allow the second battery to assist with vehicle starting or other functions. It also overcomes the problem of having 2 batteries connected in parallel (IE + TO +, - TO -) which is that the stronger will discharge through the weaker.
The second and newer system is a relay of some sort. I think its function is to connect when the charging voltage is sufficient. I think they are a bit cleverer than that and will probably bias the charging to the starting battery first before charging the auxilliary one.
Have a look on the Indespension site - its probably explained there. My guess is that you have the relay already.
The second and newer system is a relay of some sort. I think its function is to connect when the charging voltage is sufficient. I think they are a bit cleverer than that and will probably bias the charging to the starting battery first before charging the auxilliary one.
Have a look on the Indespension site - its probably explained there. My guess is that you have the relay already.
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kermit the frog
- BXpert
- Posts: 673
- Joined: Mon Aug 13, 2007 10:36 am
- Location: WORTHING WEST SUSSEX
You could find your nearest tow bar supplier and obtain a caravan secondary charging relay and fit that as per the instructions.
They are designed to allow the tow car to charge the caravan battery while towing.( SOME ONLY CONNECT THE SECOND BATTERY AFTER THE CAR STARTS UP)
But you could connect it to your second battery inside the car.
Hope this helps
Regards Kermit
PS make sure the second battery has some ventilation
charging batteries produce hydrogen gas very explosive take care
They are designed to allow the tow car to charge the caravan battery while towing.( SOME ONLY CONNECT THE SECOND BATTERY AFTER THE CAR STARTS UP)
But you could connect it to your second battery inside the car.
Hope this helps
Regards Kermit
PS make sure the second battery has some ventilation
charging batteries produce hydrogen gas very explosive take care
ALAN S an oracle of knowledge sadly missed by us all RIP Mate
Green Hornet well I don't really know.GS project gone to pastures new
Blue Streak 1996(P) XANTIA VSX TD (130K.)
Green Hornet well I don't really know.GS project gone to pastures new
Blue Streak 1996(P) XANTIA VSX TD (130K.)
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charlotte001
Second battery
Go to the local scrappy and locate a Range Rover Classic take the dual charge relay unit out of that or go to the Range Rover specialist and buy the dual charge unit cost around £20.
You're going to need some additions to the alternator to allow the charging of two batteries and have the ability to allow one to run the car and the other dormant and charge as you use it. Ill check to see if I've still got the wire diagram for dual charge.
charlotte
You're going to need some additions to the alternator to allow the charging of two batteries and have the ability to allow one to run the car and the other dormant and charge as you use it. Ill check to see if I've still got the wire diagram for dual charge.
charlotte