Watlow Series 935A User’s Manual
3 5
Thermocouple and Remote Set Point Input Field Calibration Procedure
Equipment Required:
• Type “J” Reference Compensator with reference junction at 32°F/0°C, or Type “J” Thermocouple Calibrator set at 32°F/0°C.
• Precision millivolt source, 0-50mV min. range, 0.01mV resolution.
Set Up:
1. Connect 100-240
Å
(ac), or 24-28V
‡
(ac/dc) to Terminal 7 and Terminal 8.
2. Connect the millivolt source to Terminal 1 negative and Terminal 2 positive.
3. Connect voltage source to Terminal 3 negative and Terminal 4 positive.
4. Apply power to the unit and allow it to warm up for 15 minutes.
Move to the Calibration Menu:
1. Press
.
and
,
simultaneously for 3 seconds.
2. Press
.
or
,
until
[CnFG]
is displayed.
Press and hold
ß
– press
.
or
,
to select
[`YES]
, then release
ß
.
3. Press
.
or
,
until
[`TAG]
is displayed.
Press and hold
ß
. Press
.
or
,
8 times (display shall be blank).
Calibration: (Thermocouple)
1. Press and hold
ß
,
.
, and
,
simultaneously for 3 seconds until
[TR50]
is displayed.
2. Set the mV source to 50.00mV
Î
(dc). Set the voltage source to 5.00V
Î
(dc). Allow 10 seconds for sources to stabilize. Press and
hold
ß
. Press
.
or
,
until
[`YES]
appears. Release
ß
.
3. Press
,
-
[Tc00]
shall be displayed.
4. Set the mV source to 0.00 mV
Î
(dc), set voltage source to 0.00V
Î
(dc). Allow 10 seconds for sources to stabilize. Press and hold
ß
. Press
.
or
,
until
[`YES]
appears. Release
ß
.
5. Press
,
.
[``Tc]
shall be displayed.
6. Set the MV source to 0.00 mV (if using a temperature compensator). Set calibrator to 32°F/0°C.
Set voltage source to 0.00V. Allow 10 seconds for sources to stabilize.
Press and hold
ß
. Press
.
or
,
until
[`YES]
is displayed. Release
ß
.
Calibration: (RTD)
Equipment Required:
• Precision Resistance Box with 0.01
Ω
Resolution.
1. Remove thermocouple wires from Terminal 1 and Terminal 2.
2. Connect S2 to terminal 1. Connect S1 to Terminal 2.
3. Press
,
.
[R`15]
shall be displayed.
4. Connect voltage source to Terminal 3 negative and Terminal 4 positive.
5. Set the Decade box to 15.00
Ω
, set the voltage source to 0.00V (Allow 10 seconds for sources to stabilize). Press and hold
ß
.
Press
.
or
,
until
[`YES]
appears. Release
ß
.
6. Press
,
-
[R380]
shall be displayed.
7. Set the decade box to 380.00
Ω
, set the voltage source to 5.00V. (Allow 10 seconds for sources to stabilize). Press and hold
ß
.
Press
.
or
,
until
[`YES]
appears. Release
ß
.
8. Press and hold
.
and
,
for 3 seconds to Exit calibration menu.
Calibrating the 935A and Remote Set Point Input