Omega Vehicle Security manual For Hi and Lo, The PHCN-410has a fixed, pH electrode or in

Installing the Controller

2.2.2 Making Input Connections

1.Connect the pH combination electrode to the BNC connector on the bock of the unit.

2.If using Automatic Temperoture Compensotion (ATC), connect the

100 ohm Pt RTD leads of the temperature probe to Terminals 1 ond 2 (no polarity - see Figure 2-3).

The 100 ohm Pt RTD temperature probe can be separate from

the pH electrode, built into the body of the	pH electrode or (in
selected models) built into the mounting assembly of the	pH
electrode.

If an ATC input is not provided to the meter, the temperature reading will default to 25°C. If the process temperature is constant, but not 25”C, a precision resistor can be used to simulate the appropriate temperature value to the unit. For example, if the

control process runs at O”C, a resistor with a value of 100 ohms can be wired to Terminals 1 and 2. The temperature display will show approximately 0°C. For a complete temperature versus resistance

table, consult the OMEGA Temperature Measurement Handbook and Encyclopediam.

2-4

Installing

The PHCN-410 features Automatic Temp

Compensotion; however, the temperature displayed.

2.2.3Making Output Connections

For Hi and Lo Setpoint Relays:

Connect the proper load to the NO and COM and COM terminals.

When the load is connected to the NO and COM, the re

open until the setpoint is reached. When the loa to the NC and COM, the relay is closed until the reached. The wiring configuration is application depen

The PHCN-410 has a fixed 4-20 mA output.