GE Druck ADTS 405, Service Manual

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Druck ADTS 405 Service Manual
K171 Issue No. 1 Page 5-3
Rate Calibration
8. Rate calibration should only be performed if the rate accuracy is suspect. The accuracy of
measure or controlled pressures are not affected by a rate calibration.
9. Select [RATE CAL], rate calibration takes less than two minutes.
Note: For the rate calibration to be performed, pressure and vacuum supplies need to be connected and the Ps and
Pt outlets blanked.
Calibration Check
10. The procedure for calibration check compares the entered aim values and the actual values.
With a dual channel check the [Ps END] must be selected to close a valve to protect Ps sensor.
Pressures must be applied in ascending order.
Note: Pt channel is checked in absolute mode, with Auto Zero automatically disabled.
11. Differential Qc or airspeed accuracy may be checked in normal user mode. For optimum
differential accuracy during these tests, auto zero should be ON. This is particularly significant for very
low airspeed work.
Pressure source
12.
Select the pressure source to be used during the calibration.
Internal
(1)
This is the recommended method of calibration using the pressure controllers within
the ADTS 405 to generate the required pressures for calibration. The AIM value and
RATE of change of pressure can be entered as required.
To use this mode, vacuum and dry air must be connected.
External
(2)
In this mode the ADTS 405 is in measure mode. This should only be used when
the pressure standard generates the pressure.
Channel selection
13.
Select the channel for checking:
Ps channel - absolute
14.
This enables a check of the Ps channel, using an absolute pressure standard.
(1) Connect the pressure standard to the Ps output on the front panel.
Fit the blank on the Pt output.
Pt channel - absolute
15.
This enables a check of the Pt channel, using an absolute pressure standard.
(1) Connect the pressure standard to the Pt output on the front panel.
Fit the blank on the Ps output.
Combined Ps and Pt channel - absolute
16.
This enables a combined check of the Ps and Pt channels minimising calibration time
and the errors due to pressure standard non-repeatability.
(1) Connect the calibration standard to the Pt output on the front panel.
Fit the blank on the Ps output.
(2) Apply the pressures in ascending order starting from the lowest pressure.
Each value will be used as a check point for both Ps and Pt until [Ps END] is selected.
At this point, the Ps check is complete, a valve closes to protect the Ps channel, and
the remaining points only used for the Pt channel.