Switching between ground and active

[johnvw]

Hello all,
I am sure you can assist me with this. I have recently installed ( stuck on windscreen and connector into cigarette holder ) an incar video camera. All is working nicely. Now I wish to hardwire this from the fuse box and eliminate the cigarette connection. I want to introduce a switch, so as to control when I want the unit powered up and stop the constant draw from the car battery.
DOES it matter if I break the ACTIVE lead or the GROUND lead, which is the better one, or doesn`t it matter.
I just have this unconscious thought about possible sparking.

Thank you in advance
John

[ian]

usually the active has a stripe running along its length, if it hasn't the centre wire in the cigarette plug is the active,you might have to destroy the plug to find out though .

[GTIMK4]

Hello all,
I am sure you can assist me with this. I have recently installed ( stuck on windscreen and connector into cigarette holder ) an incar video camera. All is working nicely. Now I wish to hardwire this from the fuse box and eliminate the cigarette connection. I want to introduce a switch, so as to control when I want the unit powered up and stop the constant draw from the car battery.
DOES it matter if I break the ACTIVE lead or the GROUND lead, which is the better one, or doesn`t it matter.
I just have this unconscious thought about possible sparking.

Thank you in advance
John

Although it doesn't matter which wire you choose to use as the switching wire, i always use the ground where possible. This will eliminate arcing should this wire dislodge itself and come into contact with any earthed surface. Hope this helps.

[johnvw]

Many thanks Ian and GTI Mk4,
You can always get an answer on this great Forum.
Best wishes to all
Regards John

[wai]

You should always break the active lead if you want to use a switch to control a device. The reason is that if you break the ground wire, the unit is still "hot" and any inadvertent contact with anything that can lead to ground makes the circuit live.