Post by Deleted on Jan 22, 2017 22:11:42 GMT
Here is a boaty electrical puzzle for anyone interested.
- Plugged battery voltage booster into 12v leisure circuit. This causes a very short high current draw due to it's inductive circuit.
- This in turn caused all of the 12v leisure circuit to fail. Normally this doesn't happen.
- No 12v RCD's tripped.
- After a while (a few minutes) got 8v on 12v leisure circuit
- When engine ignition was switched on (red light) the 12v leisure circuit recovered to 12.6v !
- When engine was started the 12v leisure circuit was still Ok but Amp meter shows no charging (0 amps) despite red warning light going out as usual. This is normally fine.
- Switched off ignition, 12v leisure circuit now reads 8v again.
- Removed floor panel to investigate and expose batteries to measure voltages directly.
- Before I could attach a DVM to the batteries the 12v leisure circuit recovered.
- Voltage on engine start battery = 13.3V
- Voltage on both 6v leisure batteries 6.35V (12.7 v in series -so all batteries are healthy)
This is the second time it's happened but haven't been able to investigate due to 12v leisure circuit seemingly recover after removing (disturbing) floor panel.
Floor panel is very close to top of battery terminals so I have now put a couple of plastic spacers in to ensure the panel can't disturb the batteries in some way
The floor board seems to be made out of something synthetic. It's not wood or metal, some kind of plastic which looks like Bakolite.
Things I don't understand...
1) How did I end up with 8 volts in failure mode?
2) Why would a very short high current load trigger this failure mode without tripping any RCD's?
3) How can the 12v leisure circuit be affected by the engine ignition circuit? i.e 12v leisure circuit worked when switching ignition switch on.
4) Why did ampmeter on engine panel show no battery charging in failure mode with engine running?
Everything is now fine since the failure mode disappeared. 12v leasure circuit normal. Ampmeter shows battery charging when engine started. Weird!!
- Plugged battery voltage booster into 12v leisure circuit. This causes a very short high current draw due to it's inductive circuit.
- This in turn caused all of the 12v leisure circuit to fail. Normally this doesn't happen.
- No 12v RCD's tripped.
- After a while (a few minutes) got 8v on 12v leisure circuit
- When engine ignition was switched on (red light) the 12v leisure circuit recovered to 12.6v !
- When engine was started the 12v leisure circuit was still Ok but Amp meter shows no charging (0 amps) despite red warning light going out as usual. This is normally fine.
- Switched off ignition, 12v leisure circuit now reads 8v again.
- Removed floor panel to investigate and expose batteries to measure voltages directly.
- Before I could attach a DVM to the batteries the 12v leisure circuit recovered.
- Voltage on engine start battery = 13.3V
- Voltage on both 6v leisure batteries 6.35V (12.7 v in series -so all batteries are healthy)
This is the second time it's happened but haven't been able to investigate due to 12v leisure circuit seemingly recover after removing (disturbing) floor panel.
Floor panel is very close to top of battery terminals so I have now put a couple of plastic spacers in to ensure the panel can't disturb the batteries in some way
The floor board seems to be made out of something synthetic. It's not wood or metal, some kind of plastic which looks like Bakolite.
Things I don't understand...
1) How did I end up with 8 volts in failure mode?
2) Why would a very short high current load trigger this failure mode without tripping any RCD's?
3) How can the 12v leisure circuit be affected by the engine ignition circuit? i.e 12v leisure circuit worked when switching ignition switch on.
4) Why did ampmeter on engine panel show no battery charging in failure mode with engine running?
Everything is now fine since the failure mode disappeared. 12v leasure circuit normal. Ampmeter shows battery charging when engine started. Weird!!
