Application-Specific Information - Extech Instruments MG500 User Manual

Application-Specific Information

Measuring Power Tools and Small Appliances
For small appliances, connect the GREEN (EARTH) lead to conductors and the RED (LINE) lead to
insulating material.
For single or double insulated power tools, one lead should be connected to the device's chuck,
blade, etc. and the other lead to one of the AC power cord conductors (test both conductors in
turn). Refer to the power tool application diagram below.
Connect the GREEN
lead to the chuck
AC Motor Test
Disconnect the motor from the line by:
a. Disconnecting the wires from the motor
terminals or,
b. Opening the main switch
If the main switch is opened, and the motor has a motor-starter, then the starter must be held in
the ON position. With the main switch opened, the measured resistance will include the
resistance of the motor wire and all of the other components between the motor and the main
switch. If a weakness is indicated, the motor and other components should be checked
individually. If the motor is disconnected at the motor terminals, connect the RED lead to the
grounded motor housing and the GREEN lead to one of the motor leads.
Shop for Extech products at:
AC
For 2 or 3 prong plugs, connect the
Plug
RED lead to one conductor at a time
10
ShopExtech
Connect GREEN lead
to the motor leads
Connect RED lead
to grounded housing
MG500-en-GB_v1.3 3/17
1.800.561.8187
.ca