Manual
50 Watlow Series 935A User’s Manual
Specifications
Specifications (2191)
Control Mode
• Auto-tune PID.
• PID, PD, PI, on/off.
• Countdown timer; hours:minutes, minutes:seconds.
• Timer output modes; Delay-off, Delay-on, Signal-off, Signal-on.
Agency Approvals
• UL/C-UL 508 Listed, File #E102269.
• IP65/NEMA 4X
2
rated front panel.
• CE approved:
•89/336/EEC Electromagnetic Compatibility Directive:
EN61326 Industrial Immunity, Class A Emissions
•73/23/EEC Low-voltage Directive:
EN 61010-1: 1993 Safety.
Operator Interface
• Single, seven-segment digital display, factory selectable red or green.
• Outputs/operation annunciators, three discrete LEDs.
• Three tactile feedback momentary switches.
• Front panel lock dry contact closure disables front panel operation.
Accuracy
• ±0.25% of span, ± 1 LSD, or
• Types S and T thermocouple @ < 200°C, ±0.32% of span, ± 1 LSD,
typical.
Ambient Rejection
• < 0.15°C/°C rise in ambient, or
• Types S and T thermocouple, @ < 0.47°C/°C rise in ambient typical.
Sensors/Inputs
• Sensor input sampling rate: 10 samples/second (10Hz).
• Type E, J, K, N, S and T thermocouple, grounded or ungrounded
junction.
• RTD, 100Ω platinum two-wire , DIN curve
• Remote set point input, field-selectable,
0-5VÎ (dc), scalable, 10kΩ input impedance. (Remote Input Option A
only.)
• Remote timer start dry contact closure initiates timer start. (Remote
Input Option B only.)
Input Range
Specified temperature ranges represent the controller’s operational
span.
Thermocouple
Type E -200 to 799°C
(-328 to 1470°F)
Type J 0 to 750°C
(32 to 1382°F)
Type K -200 to 1250°C
(-328 to 2282°F)
Type N 0 to 1250°C
(32 to 2282°F)
Type S 0 to 1450°C
(32 to 2642°F)
Type T -200 to 350°C
(-328 to 662°F)
RTD Resolution Platinum 0.00385 Curve
1° -200 to 700°C
(-328 to 1292°F)
0.1° -128.8 to 537.7°C
(-199.9 to 999.9°F)
Control Output
• Output update rate: 1/second (1Hz).
1 Output/Remote Input
• Switched dc logic signal, 6VÎ (dc) @ 60mA nominal, short circuit pro-
tected, non-isolated. (Watlow DIN-a-mite® power controller
compatible).
2 Output
• Switched dc logic signal, 6VÎ (dc) @ 60mA nominal, short circuit pro-
tected, non-isolated (Watlow DIN-a-mite® power controller compatible).
• Electromechanical
1
relay, Form A, 2A @ 30VÎ (dc) or, 240V~ (ac), with-
out contact suppression
3
. (Remote Input Option A only.)
• Solid-state relay, Form A, 0.5A, 24 to 264V~ (ac), without contact
suppression
3
. Off-state output impedance 31MΩ. (Remote Input Option
A only.)
Output Cycle Time
• Switched dc and solid-state relay; 5.0 second default, 0.1 second
minimum.
• Electromechanical relay; 30.0 second default, 5.0 second minimum.
Line Voltage/Power
• 100-240V~ (ac) +10%, -15%; (85-264V~ [ac]) 50/60Hz, ±5%.
• 24-28Vı (ac/dc) +10%, -15%; (20-31Vı [ac/dc]) 50/60Hz, ±5%.
(Remote Input Option A only.)
• Fused internally (factory replaceable only) time-lag type, 2A, 250V.
• Power consumption 6VA maximum.
• Data retention upon power failure via non-volatile memory.
• Switching supply speed 45kHz, ±5kHz.
Operating Environment
• 0 to 65°C (32 to 149°F).
• 0 to 90% RH, non-condensing.
Storage Temperature
• -40 to 85°C (-40 to 185°F).
Terminals
• Touch-safe set screw type, accepts 0.5 to 4mm
2
(22 to 12 AWG
wire). Torque to 0.1 Nm (4.5 in lbs).
Controller Weight
• 113 g (4.0 oz).
Shipping Weight
• 207 g (7.3 oz).
These specifications are subject to change without prior notice.










