Low voltage terminal strip (tb1) – Carrier 48/50PD05 User Manual
Page 55

55
Low Voltage Terminal Strip
(TB1)
This circuit board provides a connection point between the major
control boards and a majority of the field-installed accessories. (See
Fig. 22 and Table 25.) The circuit breakers for the low voltage
control transformers, interface connection for the Carrier Comfort
Network® (CCN) communication, and interface connection for the
Local Equipment Network (LEN) communications are also located
on the low voltage terminal strip.
C08660
Fig. 22 -- Low--Voltage Terminal Board (LVTB)
Table 25 — Field Connection Terminal Strip
TERMINAL
LABEL
DISPLAY
NAME
POINT DESCRIPTION
SENSOR
LOCATION
TYPE OF I/O
CONNECTION
PIN NUMBER
1
24 VDC Sensor Loop power
24 VDC output
J10, 17
2
IAQ
Indoor air quality sensor
return/space
4---20 mA input
J10, 16
3
Air quality & humidity sensor common
Ground
J10, 15
4
OAQ or
SP.RH
Outdoor air quality sensor or
Relative humidity sensor
field installed
4---20 mA input
J10, 14
5
RM.OC
Remote occupancy switch
field installed
24 VAC input
J10, 13
6
Switch power (ENTH, RM.OC, IAQ.S)
24 VAC output
J10, 11---12
7
ENTH or
IAQ.S
Outdoor enthalpy switch, or
Indoor air quality switch
economizer, or
return/space
24 VAC input
J10, 9---10
8*
EC.CP
Economizer commanded position
actuator (when in digital control)
economizer
2---10 VDC output
J10, 6---8
9
Economizer signal common
Ground
J10, 3---5
10*
EC.AP
Economizer position feedback (when
in analog control)
economizer
communication
2---10 VDC output
J10, 1---2
R
24 VAC power
24 VAC output
J11, 11---14
Y1
NOT USED
J11,10
Y2
NOT USED
J11, 9
W1
NOT USED
J11, 7---8
W2
HUM
Space Humidity Switch
space
24 VAC input
J11, 6
G
NOT USED
J11, 5
C
24 VAC common
24 VAC output
J11, 2---4
X
ALRM
Alarm output (normally open)
24 VAC output
J11, 1
FIRE
SHUTDOWN
1
FDWN
Fire shutdown switch 24 VAC output
supply/return
switch input
J12, 7
FIRE
SHUTDOWN
2
FDWN
Fire shutdown switch input
supply/return
switch input
J12, 6
T55
1---2
SPT
Space temperature (T55/56)
space
10k thermistor
J12, 4---5
T55
2---3
SPTO
Space temperature offset (T56)
space
10k thermistor
J12, 3---4
FAN STATUS
1---2
NOT USED
J12, 1---2
LEN
Local Equipment Network (LEN)
communication
J13, 1---3, 4---5
CCN
Carrier Comfort Network (CCN)
communication
J13, 6---8, 4---5
* Refer to Third Party Control section for more information
48/
50P
D