Condec DPDG - Manual (Page 10)

Approvals
Class I, Div. 2, Groups A-D CE approved
Appendix 1: CONDEC DPDG Calibration Procedure
Overview
Calibration adjustment of the CONDEC DPDG is performed
electronically via internal software with the case closed. There are no
mechanical adjustments; all calibration commands and adjustments
are done via the keypad, using the display to guide the user through
the calibration process.
Eight calibration points are used in the adjustment program, working
from full scale to zero at pressures equaling 100%, 87.5%, 75%, 62.5%,
50%, 37.5%, 25%, 12.5%, and 0% of full scale plus vacuum.
Note: This is an ambient temperature calibration, and should be
performed at an ambient temperature of 23° C ± 3° C (72° F ± 5° F).
Calibration outside this temperature range will invalidate the
temperature compensation program in the CONDEC DPDG.
Calibration Interval
You should check performance of the DPDG at the interval required by
your calibration program. We recommend adjustment when
measurement deviates by more than 75% of the specified accuracy, or
0.04%
Test Equipment
Verification and calibration of the CONDEC DPDG requires pressure
and/or vacuum standards able to produce and indicate pressures from
vacuum to the full-scale range of the unit under test. In order to
maintain the specified accuracy of the CONDEC DPDG, standards
should have a TUR of 4:1 or better.
Connections:
The DPDG uses a 1/4 NPT male connection in the pressure input port.
Various adapters may or may not be needed to connect to the
pressure standard. Always make sure the hose, tubing, and fittings etc
have a rated working pressure at or above the pressure of the unit.
Also it is important that there be no leaks when performing calibration;
use Teflon tape where appropriate.
Entering Calibration Mode:
After you have made your connections, turn the power on while
holding the CONFIG key. Use the arrow keys to enter the password.
The password is 101. If you have entered calibration mode correctly
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