Electrical GURU's needed... Engine Ground

[NC87GN]

Does anyone know the current capability the ground wire sattached to the back of the block? This is on a TTA where the 4 grounds are attached to the back of the motor. There are 8 wires from the engine harness that adapt to 4 ground wires attached to the block. I have an 8 position connector to adapt to engine harness but I'm not sure what current is running though the wires? Each terminal, in the connector, is rated at 13 Amps. Is that enough???

 

[GTEATER]

ttt

 

[GTEATER]

ttt

 

[kevans]

This is a shot in the dark since it's been awhile.

V = IR
R(T) = 1/R1 + 1/R2 + 1/R3 +...

So if you have 12 volts (V) and could find the resistance of each ground strap (R) using an Ohm meter you could estimate the current (I).

Example [totally off the top of my head]...u have a 12 volt battery (V) [hypothetically putting out 12 volts] and u measure each groud strap at (20,000 ohms) [just say they are all the same]...

R(T) = 1/20,000 + 1/20,000 + 1/20,000 + 1/20,000
R(T) = 0.0002

So,

V = IR
12 = I(0.0002)

Solve for I
I = 60,000 amps

Divide by 4 (for each ground strap) = 15,000 amps per strap

I made this up so don't use the numbers. I have NO idea what the numbers would be but the math should work.

HTH,
Kev

 

[salvageV6]

Find the width and thickness of the ground straps and we can possible convert that to amperes in "normal" wiring.

 

[NC87GN]

Thanks for the input kevin. Understand the theory behind calculating current but I still am looking for the current rating on those ground wires. Called Caspers Electronics and they recommended 12 AWG wire but did not know the current rating of the circuit. I'm using 14 AWG SXL wire with a contact pin to socket interface of 13 Amps per circuit. If i knew a fuse would blow at 15 Amps I would feel fine in using this connector. But if they are 30 Amp circuits then we have a problem. However that is the unknown cause I'm not sure what/where the grounds are coming from, or what they control?

Mike Banas
87GN

 

[kevans]

You know a good multimeter can give you current. Set it to it's highest amp setting and put it in series with the ground strap. Then turn it down until it give you an accurate reading.

Kev

 

[salvageV6]

I am pretty sure they are low current straps excepting the power master cable.

Gotta check the manual, most run the sensors I believe. Low current.