Question about measuring current

[Mitch//pa]

i use an external meter all the time when setting generator output and its a good idea not to trust any in dash guage until you can confirm its accurate with an ext meter. as mentioned digital multi meters tend to jump around (not give a steady reading) unless your using a good quality one but i have had success on some cheaper units you wont know till you try. put your meter in the amp mode and touch each lead to one of the junction box wing nuts on the firewall. this is essentially how the stock ammeter is wired into the circuit.

[jmeckel]

Originally Posted by Mitch//pa

i use an external meter all the time when setting generator output and its a good idea not to trust any in dash guage until you can confirm its accurate with an ext meter. as mentioned digital multi meters tend to jump around (not give a steady reading) unless your using a good quality one but i have had success on some cheaper units you wont know till you try. put your meter in the amp mode and touch each lead to one of the junction box wing nuts on the firewall. this is essentially how the stock ammeter is wired into the circuit.

You need to disconnect the stock meter first for this to work. If you do not you will get a false reading as part of the current will be flowing through the stock meter.

Also I use a FLUKE 337 DVM it works great and the noise (RFI and dirty DC) from an A does not bother it at all. I have used these meters in very high RF areas and on some very nasty looking DC and AC feeds and never have had a problem. Remember you get what you pay for!!