GE Druck ADTS 405, Service Manual

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Druck ADTS 405 Service Manual
K171 Issue No. 1 Page 5-2
CALIBRATION
General
1. For optimum calibration accuracy, the ADTS 405 should be connected to the pressure standard
using metal, PTFE or high density polyethylene hoses to avoid contamination of the internal sensors.
This is particularly important when using an EXTERNAL pressure source.
2. Allow one hour for the ADTS 405 to thermally stabilize after power on and before performing any
calibration routines.
3. The ADTS 405 incorporates an automated calibration facility that can be controlled through the
hand terminal or the IEEE 488 SCPI interface. The calibration can be performed with the ADTS 405 as
the pressure source or by using the pressure standard as the pressure source. The recommended
method is to use the ADTS 405 as the pressure source as this is the normal mode of operation of the
ADTS 405. Three different calibration functions are provided:
Calibration Check
4.
This is used to verify accuracy of the calibration without adjusting it.
Rate Calibration
5.
This is used to adjust the control transducers to the main transducer to ensure accurate rate
control. Rate calibration does not affect ADTS 405 pressure measurement accuracy.
Main Calibration
6.
This is used at depot level and should be carried out by qualified personnel.
Purging
7.
If contamination by water vapour is suspect use the calibration check facility to purge and leak
check the ADTS 405 and calibration standard as follows:
(1) Enter the calibration check facility and select the required calibration mode.
(2) Apply a vacuum from the calibration pressure source. Maintain for five minutes.
(3) Return the pressure to approximately atmospheric pressure using the calibration
media (dry air). (Do not vent to atmosphere). Repeat twice more.
(4) Apply a suitable pressure, allow to stabilize and leak test the ADTS 405 and
calibration system.