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Users Manual 
24 
Testing Insulation 
Insulation tests should only be performed on dead 
circuits. Check the fuse before testing. See Testing the 
Fuse later in this manual. To measure insulation 
resistance set up the Meter as shown in Figure 13 and 
follow the steps below: 
1.  Insert test probes in the 
p and q input terminals. 
2.  Turn the knob to INSULATION position. A battery load 
check is initiated when the switch is moved to this 
position. If the battery fails the test b and bat 
appear in the lower display. Insulation tests cannot 
be performed until the batteries are replaced. 
3.  Press r to select the voltage. 
4.  Connect the probes to the circuit to be measured. 
The Meter automatically detects if the circuit is 
energized. 
•  The primary display shows - - - - until you press 
t and a valid insulation resistance reading 
is obtained. 
•  The high voltage symbol (Z) along with a primary 
display of >30 V warns if voltage more than 30 V 
ac or dc is present. In this condition, the test is 
inhibited. Disconnect the Meter and remove 
power before proceeding. 
5.  Push and hold t to start the test. The 
secondary display shows the test voltage applied to 
the circuit under test. The high voltage symbol (Z) 
along with a primary display showing the resistance 
in MΩ or GΩ appears. The 
T icon appears on the 
lower portion of the display until t is released.  
When resistance is higher than the maximum display 
range, the Meter displays the Q symbol and the 
maximum resistance for the range. 
6.  Keep the probes on the test points and release the 
t button. The circuit under test then discharges 
through the Meter. The resistance reading appears 
on the primary display until a new test is started or a 
different function or range is selected or > 30 V is 
detected.