Owner's manual

Liquid Crystal Display
Up Down
In normal operating mode, the upper LCD displays the current sensor 1
temperature and the lower LCD displays:
the setpoint 1 and 2 temperature alternatively if 1 sensor input is selected
the current senor 2 temperature if 2 sensor input is selected.
The display is also used with the and key
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to adjust the setpoint
temperature, differential and heating/cooling modes of the operation.
OFF - backlit is turned off.
Auto - backlit is turned on for 30 secs when any key is pressed.
LCD Blue Backlit Options: set by slide switch on the front panel
ON - backlit is turned on.
ROUGH-IN WIRING
Loosen the screws on the top and bottom of the enclosure and remove the wiring
covers by swinging them away from the base(grey color) with the edges of the
covers as pivot(see Figure 1).
The base has standard 7/8” (22mm) knockouts which accept common wiring
hardware and conduit fittings. Before removing the knockouts, check the wiring
diagrams and use the chamber with common voltages.
Figure 1
Side view
Heating Mode and Cooling Mode:
Heating Mode
set by keypad
(factory setting):
The control output will turn on when the sensor temperature falls to the setpoint
temperature minus the differential amount. The control output will turn off when the
sensor temperature reaches the setpoint temperature. For example, if setpoint =
68F, Differential = 3F, then output is on at 65F and off at 68F. In other words, when the
heating mode is chosen, the differential is below the setpoint. The relay will de-
energize as the temperature rises to the setpoint. Refer to Figure 2.
Cooling Mode
The control output turned on means:
:
The control output will turn on when the sensor temperature rises to the setpoint
temperature plus the differential amount. The control output will turn off when the
sensor temperature reaches the setpoint temperature. For example, if setpoint =
75F, Differential = 2F, then output is on at 77F and off at 75F. In other words, when
cooling mode is chosen, the differential is above the setpoint. The relay will de-
energize as the temperature falls to the setpoint.
From the isolated SPDT relay output, “NO” are normally open contacts which close
and “NC” are normally closed contacts which open when the control output is on.
L.E.D. SYSTEM STATUS INDICATION LIGHTS:
RED light indicates that the SPDT relay output is energized.
One or Two sensor inputs - selected by slide switch
When one sensor input is selected, the control will operate as two stage
setpoint control. The sensor (S1) controls both relay outputs. However if
Heat/Cool mode is combined (eg. Stage 1 Heat/Stage 2 Cool), it is
recommended to add a 3 F difference between the Heat setpoint and Cool
setpoint temperature. For example, if Heat setpoint is set at 68 F and Cool
setpoint should be set at 71 F.
When two sensor inputs are selected, the control will operate as two single
stage setpoint controls. Sensor (S1) controls relay 1 output and sensor (S2)
controls relay 2 output.
°
°
°
ON (relay energized)
Setpoint
OFF
(relay de-energized)
ON
OFF
Temperature
+
-
Heating
Mode
Cooling
Mode
Figure 2: Operation of relay in according to Setpoint and Differential
Settings for both Heating and Cooling Mode
Control Outputs
The control outputs will turn on the equipment when there is a demand for
heating or cooling. When the demand is satisfied, the control outputs will turn
it off.
OPERATION
Anti-Short Cycle Delay: set by keypad
Anti-Short Cycle Delay can be set to ensure the output relay remains off for up
to 20 minutes (default is 0 mins) after relay is de-energized. This is adjustable
from 0 to 20 min with 1 minute increments. In other words, this function
establishes the minimum time that the output relay remains de-energized
before the next on-cycle. The delay is activated when the control is first turned
on, but can be skipped during the display of “2SP” at startup by pressing the
“SET” key once and go to normal operating mode (Note: SET key at this stage
will not perform any other function except terminating the time delay).
When the delay is activated:
If 1 sensor input is selected - during stage 1 delay, the Upper LCD shows
the sensor 1 temperature and “AC”(Anti-Cycle) alternatively. During stage
2 delay, the Lower LCD shows “AC”, setpoint 1, setpoint 2 alternatively.
If 2 sensor input is selected - during stage 1 delay, the Upper LCD shows
sensor 1 temperature and “AC” alternatively. During stage 2 delay, the
Lower LCD shows sensor 2 temperature and “AC” alternatively.
Also, in case there is a demand for heating/cooling, the red LED for relay
output will be blinking indicating that anti-cycle feature prevents relay from
energizing.
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Example of 2 Stage Heat Control
OFF
Setpoint 1 (69 F)°
ON (Relay Output 1 at 65 )°F
ON (Relay Output 2 at 61 )°F
OFF
Temperature
+
-
Stage 2
Stage 1
Setpoint 2 (64°F)
Differential
dF1(- 4 F)°
Differential
dF2(- 3 F)°
Example of 2 Stage Cool Control
OFF
Setpoint 1 (75 F)°
ON (Relay Output 1 at 78 )°F
Temperature
+
-
Stage 1
Differential
dF1(+ 3 F)°
ON (Relay Output 2 at 81 F)°
Stage 2
OFF
Setpoint 2 (79°F)
Differential
dF2(+ 2 F)°
Example of 1 Stage Heat/1 Stage Cool Control
OFF
Setpoint 1 (68 F)°
ON (Relay Output 1)
ON (Relay Output 2)
Temperature
+
-
Stage 2
Cool
Stage 1
Heat
OFF
Setpoint 2 (71°F)
Differential
dF1(- 2 F)°
Differential
dF2(+ 3 F)°
Minimum 3 F Gap°