Index, 20ma input field calibration procedure, Equipment required – Watlow Electric Micro-Based Autotuning Control SERIES 980/985 User Manual

Page 41: Setup and calibration, Source to, Important, Source

4-20mA Input Field Calibration Procedure

Equipment Required

Precision current source 0-20mA minimum range with 0.01 mA

resolution.

Setup And Calibration

NOTE

NOTE:

Not

all parameters

will appear. They
are dependent on

Before calibration on an installed control, make sure all data and

your unit type. Use

parameters are documented. See Setup and Operation Charts,

only the steps that

Pages 26 and 26.

apply to your unit.

Connect the AC line voltage Ll to Terminal # 4 , L2 to Terminal #7, and
Ground to Terminal

#8.

Jumper for correct line voltage. See Chapter 2.

2. Connect the voltage/current

source to

Terminal #15 and #17. Jumper

Terminal #16 to # 1 7 on the Series 980/985 terminal strip. Use regular
20 - 24 gauge wire.

Apply power to the unit and allow it to warm up for 15 minutes. After

warm-up put the unit in the CAL menu. See Figure 33 on Page 37.

Press, the MODE key until the 4A prompt is displayed.

IMPORTANT:

When the MANUAL LED is ON the-unit is automatlcally calibratlng. Your
sequence is VERY Important. Always move to the next prompt before
changing the calibration equlpment.

Press the AUTO/MAN key twice to enter the MANUAL mode. The unit is

calibrating when the MANUAL LED is ON.

At the 4A prompt, set the mA source to 4.00mA. Allow at least 10
seconds to stabilize. Press the MODE key.

At the 20A prompt, set the voltage/current

source

to 20.00mA. Allow at

least 10 seconds to stabilize. Press the AUTO/MAN key twice to exit the
MANUAL mode. This pauses calibration to allow you to exit the CAL
mode.

Appendix

WATLOW Series 980/985 User’s Manual