General Information (All Applications)
5
CTE-5202 Applications Guide, AN0912A Rev. D
Connection and Configuration
External Input (AI1)
Hot/Cold Changeover
For hot/cold air changeover on Sequence 1 or 2,
connect a changeover sensor to the AI1 input. The
sensor should be a Type III thermistor (10K ohm
strap-on sensors. (An internal 10K ohm
pullup resistor is provided on AI1.)
See, for example,
Cooling with Heating Changeover
Chilled Beam 2-Pipe Heating and
Cooling with Changeover on page 15
At power-up, the
default
mode for Sequences 1 and
2 is Cold Air mode with a default changeover set
-
point of 77° F. If the AI1 sensor reads a temperature
higher than 79° F, the Hot Air mode becomes active.
Hot Air mode stays active until the AI1 temperature
falls below 75° F. Then Cold Air mode is active until
the AI1 temperature rises above 79° F, which makes
Hot Air mode active. At power-up, if the tempera-
ture is between 75° F and 79° F, the thermostat will
assume Cold Air mode.
For continuous cold air mode, leave the sensor off.
The changeover temperature setpoint is adjustable
between 55 and 85° F in the
ADVANCE
menu, and
.
Unoccupied/Standby Setback
Contact closure across AI1 and Common initiates the
standby setback offset sequence, which causes the
cooling setpoint (in all Sequences) to increase and
the heating setpoint in Sequence 2 or 3 to decrease
by the amount of the setback offset. This setback
does not apply during the morning warm-up se-
quence.
See, for example,
Cooling with 3-Stage Reheat and
Night Setback/Setup on page 25
and
3-Stage Reheat and Night Setback/Setup on page
Connections
Standard connections to the terminal block are:
•
“Heating”
output (REE-50xx reheat relay mod-
ules and heating valves) to
AO2
and
T
(Com
-
mon)
•
“Cooling”
output (VAV dampers and cooling
valves) to
AO1
and
T
(Common)*
•
Changeover
(temperature) sensor (Type III, 10K
ohm
thermistor) and/or standby/unoccupied
setback
contact to
AI1
and
T
(Common). (See
External Input (AI1) on page 5
.)
•
24 VAC
transformer’s neutral lead to
T
(Com
-
mon) and phase lead to
~
. Alternately,
14–35
VDC
can be used with
+ connected to
~
and –
connected to
T
(Common
).
*NOTE:
AO1
also controls
heating
in morning
warm-up, changeover, and some other
configurations. For examples, see:
Beam 2-Pipe Heating and Cooling with
,
with Heating Changeover on page 37
Cooling with Morning Warm-Up on page
.
NOTE: For additional information on mounting
and installation, see the
.
~
T
T
AO2
“Heating” Output
AO1
“Cooling” Output
Common
Common
Power (AC Phase or DC +)
Input
AI1