Checking for clean grounds

[kronik 10+ year member]

Just curious, can you use a multimeter to check your grounds? Like touching it and it read a certain ohm level or some such?

I haven't had any problems yet but I just want to make sure that they're fine. I sanded both spots where I have my ground block and the negative battery. Thanks.

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[JimJ 5,000+ posts]

Yes...set it to read DC resistance, touch one probe on the metal spot you want to check, and run a negative lead back from the battery to the other probe. If it's zero ohms or close to it...bingo, there's your ground point.

 

[kronik 10+ year member]

Yes...set it to read DC resistance, touch one probe on the metal spot you want to check, and run a negative lead back from the battery to the other probe. If it's zero ohms or close to it...bingo, there's your ground point.

Danke.

 

[KaeZoo 10+ year member]

Another way to check your ground: Attach the red lead to your amp's ground terminal, and the black lead to the negative battery terminal (or to a jumper attached to the negative terminal). Set the meter for DC volts. Play the system at maximum volume; the multimeter will display your actual voltage drop between the amplifier and the battery terminal. The system has to be playing at max for this to work, and you can do it on the positive wire too.

If you discover a voltage drop higher than about .5 volts, you can measure the voltage drop at other spots to see where it's coming from...ie, between the negative terminal and the chassis connection, or on each side of the ground point itself. Measuring the DC volts of any two points in a circuit under load will show you the voltage drop between those points.

 

[kronik 10+ year member]

Yes...set it to read DC resistance, touch one probe on the metal spot you want to check, and run a negative lead back from the battery to the other probe. If it's zero ohms or close to it...bingo, there's your ground point.

For battery to frame, it reads like -.02 - .09, for ground distribution block to frame it reads -2.0 - -1.0.

Is this good?

 

[JimJ 5,000+ posts]

That's fine.

 

[kronik 10+ year member]

That's fine.

Figured as long as it was less than 0.. .. no resistance is teh pwn.

Now help me figure out my other problem.

 

[Ignatowski 5,000+ posts]

usually a frame rail works best for a GND

especially if the block is also wired to the frame