Honeywell C7046A Benutzerhandbuch

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C7046A,B,C,D AIR TEMPERATURE SENSORS
3
62-0216
Fig. 5. Connecting C7046B Air Temperature Sensor
 for mixed air, cold deck and hot deck sensing, zone 
discharge and optional remote return air sensing 
in W7080 Multizone System.
Fig. 6. Connecting C7046D Air Temperature 
Sensor to Excel 500 Control System.
OPERATION AND CHECKOUT
Operation
The C7046A,B,C Air Temperature Sensors consist of a 
thermistor sensing element mounted in a tubular probe. 
They are applied at various locations throughout single 
zone and multizone duct systems. The negative 
temperature coefficient (NTC) characteristic of the 
thermistor element causes its resistance to decrease as 
the sampled air temperature increases. This resistance 
shift is balanced with other system sensor signals by 
appropriate system logic panels to stabilize system 
control.
The C7046D Air Temperature Sensor consists of a 
platinum thin film sensor element mounted in a tubular 
probe. It can be applied at various locations throughout 
single zone and multizone duct systems. The positive 
temperature coefficient (PTC) characteristics of the 
platinum thin film element causes its resistance to 
increase as the sampled air temperature increases. This 
resistance shift is balanced with other system sensor 
signals by the Excel 500 Control System.
Checkout
Allow the C7046 Air Temperature Sensor to soak in the 
air moving through the duct or plenum for a minimum of 
five minutes before taking a resistance measurement.
1. Disconnect the sensor leadwires from the associ-
ated system components.
2. Connect an ohmmeter across the leadwires.
3. Assure nominal resistance measurements are in 
accordance with the resistance/temperature curves 
shown in Figs. 7, 8 and 9. 
4. Reconnect sensor leadwires to associated system 
components.
5. Check operation of the complete control system.
Fig. 7. C7046A,C Sensor resistance vs. temperature.
M17966A
C7046B 
(OR C7100B)
MIXED AIR
SENSOR
C7046B 
(OR C7100B)
COLD DECK
SENSOR
C7046B 
(OR C7100B)
HOT DECK
SENSOR
2
1
HOT DECK HIGH LIMIT–A7
3
4
5
6
90 
110 
130  NO JUMPER
7
8
24 Vdc
W7081 
LIMIT CONTROLLER
2
1
COLD DECK LOW LIMIT–A6
3
4
5
6
45 
55 
55  NO JUMPER
2
1
ECONOMIZER/MIXED AIR LOW LIMIT–A5
3
4
5
6
50 
55 
60  NO JUMPER
+24 VDC
+
T7080A,B 
C7046B 
(OR C7100B)
ZONE (N)
DISCHARGE
SENSOR
2
3
1
8
6
5
7
4
C7046B 
(OR C7100B)
REMOTE
RETURN
AIR SENSOR
(IF USED)
1
2
C7100B AVERAGING 
TEMPERATURE SENSOR 
MAY BE SUBSTITUTED IF 
SPACE PERMITS.
REMOTE RETURN AIR 
SENSOR USED WITH T7080B ONLY.
2
18
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
AI 1
AI 2
AI 3
AI 4
AI 5
AI 6
AI 7
AI 8
1
2
1
2
C7046D
XF521A/XF526
M2825
4000
3000
2000
1000
8000
7000
6000
5000
12000
11000
10000
9000
16000
17000
15000
14000
13000
60
50
40
70
80
10
20
30
90
100
15
20
10
25
-5
0
-10
5
30
35
RESISTANCE (OHMS)
TEMPERATURE (DEGREES)
M17969
F
C
3,000 OHMS 
AT 77 F (25 C)