Thermocouple Calibration; 4-20 Ma Output Option - Process Technology DQ15D Instruction Manual

values derived from the microprocessor oscillator. Since this is a dedi-
cated frequency, no field calibration is possible. Check that the DIP
switches are set to OFF, OFF, OFF (see page 29).

Thermocouple Calibration

Optional thermocouple sensor board needed (PCN 5418 or 5419). In-
stallation requires configuration for the specific thermocouple used. The
two wire thermocouple is polarized, therefore it is necessary to connect
the negative lead wire of the thermocouple to the #1 terminal and the
positive lead wire to the #2 terminal to maintain proper polarity for the
PCN 5418 sensor board. Connect the negative lead wire to terminal #2
and the positive to terminal #3 for the PCN 5419 sensor board.
TC
(-) TERM 2
(+) TERM 3
Equipment needed:
A precise, NIST traceable, thermocouple calibrator with suitable exten-
sion leads to match the thermocouple type used.
WARNING!
Calibration procedures require the removal of the rear cover of the
control. It also requires that power is ON, exposing the technician to
potentially lethal voltages. Exercise EXTREME CARE and wear
tested electrician's gloves whenever power is on.
Calibration procedure for a thermocouple:
Step 1: Turn OFF all power.
Step 2: Remove rear cover.
Step 3: Remove T/C sensor.
Step 4: Install the thermocouple calibrator to terminal #1 and #2
19
4-20 mA OUTPUT
(-) TERM 6
(+) TERM 7
on PCN 5418 board, or terminal #2 and #3 on 5419 sen-
sor board.
Step 5: CAREFULLY restore power to the controller, making sure
that you do not come in contact with any exposed voltage.
Step 6:
Press the increase " " and decrease " " keys simulta-
neously and hold for approximately 6 seconds. The dis-
play will indicate "AC.0". while the "0" is flashing, use
the increase key to change this to "22". Press the "SET"
key. The control display will read "CAL1".
Step 7: Adjust the thermocouple calibrator to 0.0º C (32.0º F).
Step 8: Press and hold the "SET" key for one second. The display
will read "HoLd". Wait for display to change to "CAL2".
Step 9: Adjust the thermocouple calibrator to 250.0º C (482.0º F).
Step 10: Press and hold the "SET" key for one second. The display
will read "HoLd". Wait for the display to reset and
display 250.0º C (482.0º F).
Step 11: Turn OFF power to the control and remove the thermo-
couple calibrator. Reinstall the thermocouple sensor and
the rear cover of the control. Return the control to service.

4-20 mA Output Option

The DQ15D is available with an optional 4-20 mA output signal propor-
tional to the measured (displayed) temperature. PCN 5416 or 5419 board
needed. This option is useful for source transmitting the measured tem-
perature to a current loop-sensing device, i.e. PLC, remote intelligent
display, chart recorder, etc.
Use Terminals #2
and #3 for 2 wire
1000 ohm RTD
Factory calibration is verified using an intelligent NIST traceable 4 digit
DMM, a NIST traceable sensor calibrator, and an intelligent display. The
4-20 mA OUTPUT
(-) TERM 6
(+) TERM 7
20