Bird Technologies 4412A User Manual
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1.
Connect the sine wave generator, the calibration element (P/N 4410-070),
as shown in figure 9, Calibration Set-Up.
2.
Turn on the ac voltmeter and sine wave generator.
3.
Adjust the output to 1.591 ±0.0005 volts RMS at 1000 Hz ± 100 Hz. make sure that
the generator’s “symmetry”, “offset”, and “waveform” controls are set to provide
a symmetrical sine wave with zero DC offset.
Note:
Leave the equipment in this condition to stabilize for the
period of time recommended by the manufacturers but not less
than five minutes.
4.
Turn the range selector switch to the “100" position and allow the wattme-
ter a minimum of five minutes to stabilize.
Note:
The wattmeter does not need to be connected to the calibra-
tion setup for the five minute warm-up period.
5.
After the equipment has stabilized, check the battery in the wattmeter by
momentarily placing the range switch in the BATT position. The meter
pointer should travel well into the “BATTERY TEST” region of the meter
scale. If not, turn the unit off and replace the battery.
6.
Return the switch to the “100" position.
7.
Allow the unit’s internal circuitry to stabilize for another five minutes if the
battery was replaced.
8.
Insert the calibration element into the wattmeter and rotate it in either
direction until it stops.
9.
Recheck the sine wave generator for the proper 1000Hz ±100Hz output set-
tings, then readjust the amplitude as necessary until the voltmeter reads a
stable 1.591 ± 0.0005 volts.
10. Turn the 4410-070 calibration element 90° to short circuit the spring contact
in the line section to the line section body.
11. Set the range switch to the “1" position.
12. Adjust the sine wave generator’s output to the wattmeter’s calibration voltage.
Note:
This calibration voltage is recorded on a label inside the instru-
ment’s back cover. If no calibration voltage is listed, adjust the sine
wave generator’s output to 0.1591±0.00005 volts RMS.
13. Rotate the calibration element in either direction until it stops.
14. Adjust R26 until the meter pointer rests at ”1" on the upper scale. Calibration
is complete.