18
Table 1 — Thermistor Resistance vs Temperature Values for Space Temperature Sensor, Return-Air
Temperature Sensor, and Supply-Air Temperature Sensor
PRIMARY AIR TEMPERATURE SENSOR INSTALLA-
TION — A primary air temperature (PAT) sensor is used on a
zone controller which is functioning as a Linkage Coordinator
for a non Carrier Network/Linkage compatible air source. The
part number is 33ZCSENPAT. See Fig. 19.
When used on a zone controller, try to select a zone control-
ler which will allow installation of the PAT sensor in the main
trunk, as close to the air source as possible. See Fig. 20.
DUCT
TEMPERATURE
SENSOR
(33ZCSENDAT)
INSTALLATION — The 33ZCSENDAT Duct Air Tempera-
ture Sensor is required for cooling only applications on non-
Carrier dampers. The sensor is used for supply air monitoring.
The sensor has an operating range of –40 to 245 F (–40 to
118 C) and includes a mounting grommet and 75-in. cable. The
duct temperature sensor must be installed in the supply air duct.
See Fig. 21 for sensor details.
The duct temperature sensor should be moved to a location
which will provide the best sensing of the supply-air tempera-
ture during heating and cooling.
For systems using a ducted supply, the duct temperature
sensor should be located in the supply duct downstream of the
discharge of the air source and before the bypass damper to
allow good mixing of the supply airstream.
The 33ZCSENDAT duct sensor is a small epoxy sensor that
is 1
1
/
4
-in. long. A grommet is provided for filling the hole
around the sensor cable after the sensor is located in the duct.
See Fig. 22 for mounting location.
Do not run sensor or relay wires in the same conduit or race-
way with Class 1 AC service wiring. Do not abrade, cut, or
nick the outer jacket of the cable. Do not pull or draw cable
with a force that may harm the physical or electrical properties.
Avoid splices in any control wiring.
Perform the following steps to connect the duct temperature
sensor to the bypass controller:
1. Drill or punch a
1
/
4
-in. hole in the supply duct. See
Fig. 22. Duct sensor can be installed to hang from top of
duct or from the sides. Sensor probe can touch side of
duct.
2. Push sensor through hole in the supply duct. Snap the
grommet into the hole until it is secure. Pull on the leads
of the duct sensor until the sensor is snug against the
grommet.
3. Connect the sensor leads to the bypass controller’s termi-
nal board at the terminals labeled SAT and GND. See
Fig. 5-13 for wiring. If extending cable length beyond
8 ft, use plenum rated, 20 AWG (American Wire Gage),
twisted pair wire. Sensor wiring does not have polarity.
Either lead can be wired to either terminal.
4. Neatly bundle and secure excess wire.
5. Using electrical tape, insulate any exposed lead to prevent
shorting.
6. Connect shield to earth ground (if shielded wire is used).
SUPPLY AIR TEMPERATURE (33ZCSENSAT) SENSOR
INSTALLATION — The 33ZCSENSAT supply air tempera-
ture sensor is required for reheat applications or stand-alone
operation. The sensor has an operating range of –40 to 245 F
(–40 to 118 C) and includes a 6-in. stainless steel probe and
cable. The sensor is factory-supplied but must be relocated for
ducted heat. The SAT must be installed in the duct downstream
from the air terminal. The SAT sensor is also sometimes called
a duct air temperature sensor. Part number 33ZCSENSAT may
be used in place of the factory-installed sensor.
The SAT sensor probe is 6 inches in length. The tip of the
probe must not touch the inside of the duct. Use field-supplied
bushings as spacers when mounting the probe in a duct that is
6 in. or less in diameter.
If the unit is a cooling only unit, the SAT is not required.
If the unit is equipped with electric reheat, ensure that the
sensor is installed at least 2 ft downstream of the electric heater.
See Fig. 23 for the sensor location in this application.
If the unit has an octopus connected directly at the
discharge, install the sensor in the octopus. If the unit has an
electric heater, the two-foot minimum distance between the
sensor and the heater must be maintained. See Fig. 23 for the
sensor location in this application.
TEMP
(C)
TEMP
(F)
RESISTANCE
(Ohms)
–40
–40
335,651
–35
–31
242,195
–30
–22
176,683
–25
–13
130,243
–20
–4
96,974
–15
5
72,895
–10
14
55,298
–5
23
42,315
0
32
32,651
5
41
25,395
10
50
19,903
15
59
15,714
20
68
12,494
25
77
10,000
30
86
8,056
35
95
6,530
40
104
5,325
45
113
4,367
50
122
3,601
55
131
2,985
60
140
2,487
65
149
2,082
70
158
1,752
Disconnect electrical power before wiring the bypass con-
troller. Electrical shock, personal injury, or damage to the
fan coil controller can result.
Disconnect electrical power before wiring the zone control-
ler. Electrical shock, personal injury, or damage to the zone
controller can result.
Содержание 3V VVT 33ZCVVTZC-01
Страница 59: ......
