CHART TRIFECTA 2K, Руководство по обслуживанию

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Trifecta 2K
Pressure Transmitter
To check a pressure transmitter, measure the voltage from the appropriate input channel to
the terminal GND. The probes of the voltmeter can be placed directly on the terminal screw
heads. Either of the two GND terminals can be used as they are common internally to the PLC.
With the measured voltage, calculate the pressure by the following equation:
For example, if the voltage measured between U5 and GND was 3.600 volts on a system in
nitrogen or argon service, it would mean that the bulk tank should be at a pressure of:
If the pressure gauge on the bulk tank does not read approximately 100 psig, there is a
possibility that the transmitter is not functioning properly. A quick view table is provided for
your information on the next page.
Differential Pressure Transmitter
To check a differential pressure transmitter, measure the voltage from the appropriate input
channel to GND. The probes of the voltmeter can be placed directly on the terminal screw
heads. Either of the two GND terminals can be used, as they are common internally to the PLC.
With the measured voltage, calculate the differential pressure by the following equation:
For example, if the voltage measured between U1 and GND was 3.200 volts, it would mean
that the liquid level of Laser-Cyl #1 is:
If the liquid level gauge on Laser-Cyl #1 does not read approximately 15 inches of water,
there is a possibility that the transmitter is not functioning properly.
Note that the transmitter and gauge readings may not match exactly. A quick view table is
provided for your information on the next page.
Voltage x 2 - 4
16
23
Pressure =
3.600 x 2 - 4
16
Pressure =
Voltage x 2 - 4
16
Differential Pressure =
x 500
x 500 = 100 psig
x 100
3.200 x 2 - 4
16
Differential Pressure = x 100 = 15 inches of water