Simple electrical question

1. ## Simple electrical question

Someone please remind me what order electrical wires (eg. battery cables) should be attached/removed?

Say, I want to remove my battery, then later reinstall it. Do I remove positive the positive lead first, etc.?

I looked in my mechanic's book for the answer, but I think the question is so mind-numbingly simple it's assumed I know already. Duuuhhhhh

2.

3. I read somewhere usually ground first, then the positive.

Correct me if Im wrong.

4. in case of a surge/short, you always want your battery grounded, so that the extra power doesn't fry your battery. it should be power wire off first, then ground wire, when taking battery out. when re-attaching, ground first, then power wire.

5. So, which is ground and which is power? +ve or -ve?

6. +=postive take that off first -=negative take that off next installation is the exact opposite

7. well . . . from my training* and experience you should remove the earth (-) side first. and connect it last

the reason is that when you are wrenching away on the earth lead, if the wrench should touch the vehicle body/chassis nothing will happen. however, if you wrench away on the positive connection first and your wrench should touch anything grounded then you have a red hot wrench and a possibly explosive battery . . . . . .

carlo: there can not be a 'surge' if there is not a complete circuit

* heavy duty mechanic

8. in trade school we were always told negative off first, negative on last..... taking the battery out, negative off first, putting the battery in negative on last

9. hey, i learned something new...i was going by based on my own reasoning but now i know the real answer...thanks!

10. Originally Posted by CB450
hey, i learned something new...i was going by based on my own reasoning but now i know the real answer...thanks!
my pleasure

life would be boring if there was nothing left to learn, eh . . . . . . ?

11. Originally Posted by iceneweb
well . . . from my training* and experience you should remove the earth (-) side first. and connect it last

the reason is that when you are wrenching away on the earth lead, if the wrench should touch the vehicle body/chassis nothing will happen. however, if you wrench away on the positive connection first and your wrench should touch anything grounded then you have a red hot wrench and a possibly explosive battery . . . . . .

carlo: there can not be a 'surge' if there is not a complete circuit

* heavy duty mechanic
Thank you. I was going to argue the other responses, but meh, I'm too lazy.

12. negative (ground, black) off first, and on last.

13. Originally Posted by iceneweb
well . . . from my training* and experience you should remove the earth (-) side first. and connect it last

the reason is that when you are wrenching away on the earth lead, if the wrench should touch the vehicle body/chassis nothing will happen. however, if you wrench away on the positive connection first and your wrench should touch anything grounded then you have a red hot wrench and a possibly explosive battery . . . . . .

carlo: there can not be a 'surge' if there is not a complete circuit

* heavy duty mechanic

Earth wire ? you haven't been trying to contact the mother ship again have you?

14. Just don't do when I am tired and confuse the black=ground of 12v systems with black=hot of 100+v systems.

-Sandworm

15. yeah, always ground first. Just for those who don't know, electricity actually flows from ground to positive. It's all about the flow of electrons. This is why we disconnect ground first.

16. You will always remove the ground black wire first. The reason is due to the fact that you may touch part of the frame which is also grounded with your wrench while removing it. While removing the ground lead should your wrench touch the frame there will be no electrical circuit completed and hense no spark (it's the spark that has been known to ignite fumes and blow the shit out of your face). Once the ground wire has been removed your frame is no longer part of the circuit and if you should accidently touch your wrench to the frame while removing the positive now you will still not create a spark once again saving that lovely face of yours.

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