Brooks Instrument IPT122 2 Indicating Pressure Transmitters" - Manual (Page 17)

Installation and Operation Manual
X-PR-IPT122-eng
Part Number 541B151AAG
April, 2010
IPT122 Series
3-1
Section 3 Calibration
3-1 Gauge Alignment
Since the IPT122 is an electromechanical device, the gauge linkage may
move from the home position during shipment or installation. Pressure cycle
the gauge a few times to assure the movement is in its home position.
3-2 Adjustments and Calibration
The IPT122 is factory calibrated for the proper output. Field calibration is only
necessary if ZERO and SPAN adjust potentiometers have been changed or
different output is required.
3-2-1 ZERO Adjustment Potentiometer
(See Figures 2-1, 3-1 and 4-1)
The IPT122 is factory calibrated for the proper output. Field calibration is only
necessary if ZERO and SPAN adjust potentiometers have been changed or
different output is required.
3-2-2 SPAN Adjustment Potentiometer
(See Figures 2-1, 3-1 and 4-1)
The SPAN adjustment sets the output signal to the high level when full scale
pressure is applied to the gauge Calibration Procedure
1. Turn on power and pressure cycle the IPT a few times to verify a reading
at the voltmeter and to assure the mechanical movement is in its home
position.
2. Set pressure to zero (remove all pressure).
3. Rotate the ZERO adjust potentiometer CW to increase, or CCW to
decrease the output signal. Set the output to the low level
(for example, 4 mA).
4. Apply full scale pressure to IPT.
5. Rotate the SPAN adjust potentiometer CW to increase, or CCW to
decrease the output signal. Set the output to the high level (for example,
20 mA).
6. Set pressure to zero and repeat the calibration procedure until accuracy
of SPAN and ZERO points is obtained.