On a computer board with an AC test point, where do you put the other lead of the DMM? Since AC doesn't use ground I wouldn't ground it. Do I just find a connector pin that is the AC return line? For example the rectifier board on early Bally's have TP4 which is 7.3 VAC. I would put one lead on TP4 but where would I put the other lead?

Thanks.

#2 11 years ago

JMS

sneljo82

Inactive member

Swifterbant

11y 14,150 151 3

put the other lead on ground, for example a screw on the same board.

#3 11 years ago

AMS

barakandl

nvram.weebly.com

12y 132K 10,417

In this case the normal ground is "neutral" and the "earth ground". Just use your ground braid in the cabinet / head.

#4 11 years ago

KAG

kguenther6

Pinside+ Frequent

Burlington, KY

12y 73,550 664 17 25

I thought the ground was only for checking DC. Thanks for the clarification.

#5 11 years ago

AMS

barakandl

nvram.weebly.com

12y 132K 10,417

Well in say a wall outlet you normally probe the hot side and neutral side. Ultimately the neutral is connected to the earth ground at the breaker box (i think i am no electrician).

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