Form Number TM61320-2-4
Rev 4 February 2008
Page 17
Calibration Procedure
Recalibrate your meter:
It is recommended that the multimeter be calibrated once each year.
1. Perform calibration at an ambient temperature of 23°C±2°C and a relative humidity of 73% or
less.
2. Disconnect the test leads and turn the meter off. Remove the test leads from the front terminals.
3. Position the meter face down. Remove the three screws from the case bottom.
4. Lift the end of the case bottom until it gently unsnaps from the case top at the end nearest the
LCD.
5. Lift the circuit board from the case top. Do not remove the screws from the circuit board.
(A) DCV Calibration (Adjust VR1)
(refer to Figure 4 & 5)
1. Set the circuit board rotary switch
"arrow"
to the
"V"
position of circuit board.
2. Set the output of DC calibrator for 300.0V±0.02% and connect to
V
Ω
Hz
and
COM
input terminals on
meter.
3. Using a small flat-tipped screwdriver adjust the potentiometer
VR1
until the display reads 299.0 or
300.1.
4. Disconnect the DC calibrator from the meter.
(B) ACV Calibration (Adjust VR2)
(refer to Figure 4 & 5)
1. Set the circuit board rotary switch
"arrow"
to the
"V"
position of circuit board.
2. Set the output of AC calibration for 300Vrms 50Hz (61-320) 300Vrms 50Hz (61-322/61-324) and
connect to
V
Ω
Hz
and
COM
input terminals on meter.
3. Using a small flat-tipped screwdriver adjust the potentiometer
VR2
until the display reads 299.9
or 300.1 (61-320) / 299.9 or 300.1 (61-322/61-324).