Auto Mode - Electro-Tech systems 406D Operating Manual

depress CHG. This function also limits the Static Decay Meter ability to
measure decay times longer than this time out.
8. When the CUTOFF threshold selected is reached, the unit will automatically
switch to the TEST OVER state, the Sensor Head Shutter will close, and the
Decay Time measurement, in seconds, will be displayed on the DECAY
TIME readout. The unit will remain in the TEST OVER state until the
ZERO/STBY or CHG button is depressed.
9. To repeat the test measurement, depress the CHG button and, when the
SAMPLE CHARGE meter reads full scale, depress TEST. For the greatest
accuracy,, it is recommended that the zero calibration point be checked
between decay time measurements and the ZERO control adjusted if
necessary. As noted earlier, calibration of the zero point is always done with
the system in ZERO/STANDBY.
NOTE: For additional information on sample testing, please refer to Section
4.0 "Testing Hints and Other Tests".
3.3

AUTO Mode

In this mode, the Model 406D Static Decay Meter will conduct up to 9
measurement cycles automatically, including automatic zero calibration. This
mode cannot be used with samples that have an initial or a residual charge.
3.3.1 Initial Set Up
Follow the procedures outlined in Section 3.1.
3.3.2 Full Scale Calibration
With the unit in MANUAL and ZERO/STANDBY, zero the SAMPLE
CHARGE meter by adjusting the ZERO control. Select the CHARGING
VOLTAGE polarity by depressing either the + or - button.
Wait approximately 2 seconds, then set the CHARGING VOLTAGE
meter to either + or - 5kV using the HIGH VOLTAGE ADJUST Control.
Depress the CHG button and adjust the FULL SCALE calibrate control so
that the SAMPLE CHARGE meter reads ±5kV. Unless this adjustment is
properly made before the AUTO mode is selected, the Automatic Mode
may not function properly. The FULL SCALE ADJUST knob should point
approximately to the NORM position. For non-planar material, other
settings will apply to achieve a full scale reading.
3.3.3 Sample Testing
After the unit has been calibrated, select the AUTO mode by depressing
the AUTO/MAN button. The button will latch in the down position, the
SAMPLE CHARGE meter will read zero, the unit will return to the
ZERO/STBY state and the AUTO mode readout will be illuminated and
display zero.
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