Ecom Instruments CP 440 Instruction Manual page 10

Calibration Interval
You should check performance of the unit 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 CP 440 requires pressure and/or vacu-
um 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 CP 440, standards should have a TUR of 4: or better.
Connections:
The PI uses a /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 pass-
word is 0. If you have entered calibration mode correctly the display
should look as shown below. The pressure value displayed will be the
full-scale value of the gauge.
Procedure:
Screens shown in this manual represent the displays shown with a 500
psi Gauge. The CP 440 will prompt the technician for the appropriate
pressure at each calibration point.
PSI
500.00
CAL MODE
Use the Pressure Standard to output 500.00 psi (00%). After the output
has stabilized, press the ENTER key to continue. As the unit takes rea-
dings, the screen will show -------. When the readings are complete the
screen should look as shown in the illustration that follows.
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