Can anyone tell me what voltage i should be getting from my towing vehicle at the 12s socket, the frige voltage is as normal 12v. thanks, chas.
charging the caravan battery.
- Thread starter chas1
- Start date
If the car engine is off, then the battery will produce a voltage between 12.6 and 12.0 volts (or lower) depending on charge state. A caravan GEL leisure battery usually produces between 12.9 and 12.2 volts (different chemistry and plate geometry)
If the engine is running, fast idle or better, then the alternator will typically be producing 13.4 to 13.8 volts - and assuming there is no or little voltage drop - you should see 13+ volts on the 12S socket.
Robert
If the engine is running, fast idle or better, then the alternator will typically be producing 13.4 to 13.8 volts - and assuming there is no or little voltage drop - you should see 13+ volts on the 12S socket.
Robert
You should have "battery voltage"---wheather it be 12v(ish) at idle or engine not running and "charging voltage" 13-14v when above fast idle speed.
What you don't need is a significant voltage drop through your wiring or relay so to check for this you can either compare the reading at battery terminals to the reading at the 7s pin and earth at a constant engine speed or better to connect a voltmeter between your battery poss and 7S pin. Your reading should be below 0.5 v.
at your 7S socket
What you don't need is a significant voltage drop through your wiring or relay so to check for this you can either compare the reading at battery terminals to the reading at the 7s pin and earth at a constant engine speed or better to connect a voltmeter between your battery poss and 7S pin. Your reading should be below 0.5 v.
at your 7S socket
- Mar 14, 2005
- 19,123
- 4,325
- 50,935
Hello Oldfogey,
What you are suggesting will work but you must take some additional precautions;
Ideally contain the battery is a closed box, which has a vent pipe from the top to the outside. This is to allow the hydrogen gas that can be given off a chance to escape and not build up to present an explosion or fire hazard.
The connection cables should be fully insulated even over the battery clips, to minimise the possibility of accidentally shorting the battery or the car electrics. For added protection both the + & - wires should have 10 or 16A fuses in circuit, again to protect from faults of accidental short circuits.
The battery, and the box must be secured so that it does not move when cornering or breaking.
I use a similar system, but I make up a cable set into a 12S plug so that is only plugged in when I intend to charge the battery. This means there is no additional car wiring, other than the normal tow sockets.
Check that the boot seal is sufficiently compliant to allow both the 12V cable and the vent pipe to be held in place without damage when the boot/tailgate is closed.
What you are suggesting will work but you must take some additional precautions;
Ideally contain the battery is a closed box, which has a vent pipe from the top to the outside. This is to allow the hydrogen gas that can be given off a chance to escape and not build up to present an explosion or fire hazard.
The connection cables should be fully insulated even over the battery clips, to minimise the possibility of accidentally shorting the battery or the car electrics. For added protection both the + & - wires should have 10 or 16A fuses in circuit, again to protect from faults of accidental short circuits.
The battery, and the box must be secured so that it does not move when cornering or breaking.
I use a similar system, but I make up a cable set into a 12S plug so that is only plugged in when I intend to charge the battery. This means there is no additional car wiring, other than the normal tow sockets.
Check that the boot seal is sufficiently compliant to allow both the 12V cable and the vent pipe to be held in place without damage when the boot/tailgate is closed.
Hi John L
Seems to be confusion with your answer to Oldfogey... Because there is no comment from Oldfogey or has it been removed?
Seems to be confusion with your answer to Oldfogey... Because there is no comment from Oldfogey or has it been removed?
That's because my comment is in GeneralRunning on the Battery, not here!
It concerns the possibility of loading the battery into the car to recharge while you go off for a day out.
It concerns the possibility of loading the battery into the car to recharge while you go off for a day out.
Facebook
Twitter