Conductivity/Resistivity Analyzer/Controller

6.3 Wiring Analog Inputs and Outputs

Introduction

Every 9782 Analyzer/Controller requires input signals from the cells.

In addition, some 9782 models provide from one to three analog output signals (current and/or voltage) that can be used to retransmit process variables, or to provide Current Adjusting Type control (see 1.5.3).

Wiring these analog inputs and outputs is described here. Wiring relay outputs is described in 6.4.

Cell identification significant to computed value

The 9782 can compute a value (choices listed below), then display the value, and, if desired, use it as the basis for control or alarming. (Sample applications are shown in Appendix B.) Each of these computed values is calculated based on the process variable value measured by both cells. Therefore, it matters which cell is considered “Cell 1” and which is “Cell 2”. The Analyzer/Controller determines the cell’s identity based upon which terminals receive the cell’s input (see Figure 6-1). If you have set up the 9782’s software to use a computed value, be

sure to wire the cell leads correctly.

The available computed values are:

Cell1

RATIO: ratio between the values measured by the cells; Cell2

DIFFERENCE: difference between the values measured by the cells; Cell1 Cell2

 

 

Cell1

x100

%PASSAGE: computed percent passage: Cell2

 

 

(1

Cell1

)x100

 

 

%REJECTION: computed percent rejection: Cell2

PPMCO2: computed parts per million carbon dioxide (9782C-S0 only)

Procedure

Follow the procedure in Table 6-2 to install analog I/O wiring.

WARNING

While the unit is powered, a potentially lethal shock hazard exists inside the case. Do not open the case while the unit is powered. Disconnect power before installing I/O wiring. More than one switch may be required to disconnect power.

6-4

9782 Series Conductivity/Resistivity Analyzer/Controller - Operator’s Manual

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Honeywell 9782 Series manual Wiring Analog Inputs and Outputs, Cell identification significant to computed value