Lochinvar Crest 751 - Page 41

41
Installation & Operation Manual
7 Field wiring (continued)
1
2
3 4
5
6
7
8
9
10
11
12
13
14
15
16
ALARM
CONTACTS
RUN TIME CONTACTS
TANK
THERMOSTAT
ENAB LE LOUVER
PROVING LOUVER
RELAY
AUX
SWITCH 1
AUX SWITCH 2
40 39
38
37 36
35 34
33
32
31
30 29 28 27
26
25 24
23 22
21 20
19
18 17
CASCADE
SYSTEM PUMP
IN
BMS
IN
OUTDOOR
SENSOR SENSOR
SENSOR
SENSOR
TANK
SYSTEM SUPPLY
SYSTEM RETURN
BOILER PUMP
OUT
OUT
RATE
MODBUS
SHIELD SHIELD B A -
+ +
-
-
- + +
SHIELD
SHIELD B
A
BUILDING
MANAGEMENT
SYSTEM
TANK
THERMOSTAT
ENABLING
DEVICE
LOUVER
PROVING
SWITCH
LOUVER
RELAY
AUX
SWITCH 1
AUX
SWITCH 2
FROM PREVIOUS BOILER TO NEXT BOILER
A B B
A
SHIELD
SHIELD
0-10V INPUT SYSTEM PUMP OUTDOOR SENSOR
TANK SENSOR SYSTEM SUPPLY SENSOR SYSTEM RETURN SENSOR
0-10V OUTPUT
BOILER PUMP
MODBUS
COMMUNICATION BUS
SHIELD
A
B
B A
SHIELD
Figure 7-3 Low Voltage Field Wiring Connections
* See page 18 for special instructions when common venting Crest boilers.
*