Operation - Extech Instruments 380375 User Manual

Operation

Note: Ensure that the circuit under test does not include devices or components that can
be damaged by 5000VDC; such devices include power factor correction capacitors, low
voltage mineral insulated cables, electronic light dimmers, ballasts and starters for
fluorescent lamps.
Connecting the Test Leads to the meter
The Black (Earth) and Red (Line) test leads connect to the meter in the lead compartment
located on the back of the meter (the meter jacks are color coded). NOTE: The Green
(Guard) lead is typically not used. Do not connect this test lead to the meter unless
absolutely certain it is going to be used. For more information, continue reading this
Operation section and the Applications section to follow.
Connecting the Test Leads to the device under test
The Black (Earth) lead is connected to the conductive material. The Red (Line) lead is
connected to the insulating material. The Green (Guard) lead is at the same potential as
the negative terminal (0V) and, when required, is used to prevent erroneous readings by
removing parallel leakage paths from the measurement.
Insulation Resistance Measurements
1. Connect the test leads to the meter and the device under test.
2. Press the ON / TEST button to turn the unit on. The
unit will display the turn-on screens and then stop at
the "Select Test" display.
3. Select the desired test voltage by pressing the 500V,
1KV, 2.5KV, or 5KV button. The screen will briefly
display the selected test voltage and then will proceed
to the "Connect Leads Testing for LIVE" display. If the
circuit is "live" the display will indicate "Live Warning... Circuit Live" and the meter will
beep. If this occurs, remove the test leads and press the ON / TEST button.
4. Press the ON / TEST button to apply the voltage and begin the test. The meter will
beep every 2 seconds which indicated high voltage is on the test leads and the meter
will intermittently buzz while the high voltage is being generated.
5. On the display, elapsed test time appears on the
upper right, the resistance reading appears on the
upper left, the selected voltage is shown on the lower
right and the bar graph indicates the actual voltage
present on the test leads.
6. At the completion of the test the meter will discharge
the device under test and the display "HOLD". Do not
remove the test leads until the bargraph disappears
(complete discharge) and "HOLD" appears in the display.
7. The meter automatically discharges the system at the end of the test. The test ends
when one of the following occurs.
a. After approximately 10 seconds in the Enersave
b. After approximately 100 seconds in the continuous mode.
c. When the red ON / TEST button is pressed.
TM
mode.
4
Select Test
2.5kV, 1kV, 500V
C o n n e c t L e a d s
T e s t i n g f o r L I V E
R = 1 0 8 . 2 M Ω
0 █ █ █ █ █ █
R = 1 2 8 . 4 M Ω
0 H O L D
380375 V1.5 3/04
5kV
6 . 5 s
5 0 0 V
7 . 4 s
5 0 0 V