Sec. 11.1
CALIBRATION PROCEDURE
The procedure should be performed at an ambient temperature of
25°C ± 2°C and at a relative humidity of less than 80%. Allow the
instrument to stabilize at this temperature for a minimum of 30 min-
utes.
1. Remove the back case screw and carefully pry up the back
case.
2. Set the range switch to the "200mVdc" position.
3. Set the output of the DC calibrator for 190.0mV ± 0.02% and
connect it to the "V-Ω" and "COM" input terminals.
4. Adjust R47 until the display reads 190.0mV ± 1 digit.
5.
Carefully inspect the other DCV ranges. Your readings should
be within specification ±0.5% + 1 digit.
6.
There is no adjustment for ACV. Calibrate DCV first.
7.
Carefully inspect the ACV ranges. Your readings should be
within ± 1.2% + 4 digits of the ACV calibration source.
8.
Set the output of the DC calibrator for 1.9 ±0.02% and connect
it to the "10A" and "COM" input terminals.
9.
Adjust R001 (shunt resistor) until the display reads 1.9A.
10. If the reading is over 1.9A, add solder to R001. If the reading
is under 1.9A, shave away lightly some of the solder and metal
from R001.
11. Carefully inspect the other DCA ranges. Your readings should
be within specification ±1.0% + 1 digit.
12. Turn off calibrator and disconnect from the DMM.
13. Install the back case and insert the back case screw.
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DM4400 04_06 5/3/06 1:10 PM Page 20
