Installation manual

900M050U00  Athena Controls, Inc. 18-1

18. Calibrating the Controller

18.1 Introduction

You do not have to calibrate every new controller. When a controller was ordered, you

specified an input type for which the unit was calibrated at the factory. This is not the

specific type chosen with the input menu tYPEtYPE (type) parameter, such as J

thermocouple, or 0 to 20 mA linear. In the context of ordering the controller, “type” refers

to these choices:

• RTD

• compressed RTD (RTD with decimal support)

• thermocouple

• millivolt linear

• volt linear

• current linear input

The controller was calibrated at the factory for the type of input specified. If you use the

controller with a different type of input, you must recalibrate as described in this section

unless you ordered the “Calibrate All” input option.

For example, if you specified when you ordered the controller that you planned to use a

thermocouple as the sensor, then you can use the input menu tYPEtYPE (type) parameter to

choose any thermocouple type: B, C, E, J, K, N, NNM, R, S, T, or Platinel II. The

controller will be calibrated appropriately at the factory. However, if you ordered

thermocouple calibration, but decide to use the controller with an RTD sensor, then you

must recalibrate before using the controller. The “low calibration” procedure will offset

zero if necessary, and the “high calibration” will perform the span adjustment.

If you change the input type (including changing linear input type) for a 16C, 18C, or 25C

controller, you might also have to change input jumper settings. See 5.3 for details.

WARNING

All wiring should be done by an experienced technician and be installed

in accordance with national and local electrical codes. To avoid serious

personal injury and damage to equipment, follow all warnings and

cautions provided in the controller installation manuals.

To determine whether the controller in hand was calibrated at the factory for all input types, check the

model number on the label on the controller. The meaning of each character in the model number is in

the installation manual supplied with the controller.