Presys PCA-570-RM Technical Manual page 47

The current input readings can be scaled to pressure using the SCALE option (see 2.4.4.a). In this way the
error between the input and output of the pressure transmitter is easily calculated.
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b) Pressure Switch Check
Pressure switches are instruments with a pressure input and a relay alarm. The relay is activated whenever
the input pressure goes above or below a certain alarm setpoint.
Connect the relay output of the pressure switch to the contact input of the PCA-570, SWITCH terminals, and
make the pneumatic connections illustrated in the following figure.
Fig. 30 - Pressure Switch