Product Overview
Table Of Contents
- System 450 Overview
- Compact Modular Plug-Together Design
- Multipurpose and Field Configurable
- Global Design
- System 450 Applications
- System 450 Control Modules
- Expansion Modules and Outputs
- System 450 Power Module
- System 450 Sensors and Transducers
- System 450 Control Systems
- Standard System 450 Control Systems
- System 450 Reset Control Systems
- Hybrid Analog Output and High Input Signal Selection Control
- System 450 Differential Control
- Ordering Information
- Technical Specifications
System 450™ Series Modular Controls Product Bulletin10
System 450 Reset Control Systems
Figure 12 shows a System 450 Reset Control system
that uses an outdoor air temperature master sensor
and a supply water temperature sensor configured to
reset the boiler supply water temperature relative to the
outdoor air temperature. This control system can also
be configured to use the Load Balancing feature to
equalize the time that each of the four boilers run.
Figure 12: System 450 Reset Control System Example for a Three-Stage Boiler
with or without Load Balancing
LC1
LNO1
LNC1
LC2
LNO2
LNC2
240
V
AC
120
V
AC
LC1
LNO1
LNC1
LC2
LNO2
LNC2
L2
L1
L2
L1
L2
L1
L2
L1
L1 L2
C450RCN-x
Reset Control Module C450YNN-1
Power
Module
C450SCN-x
Expansion Module
Sn-1
Sn-2
Sn-3
Relay
Output 1
Relay
Output 2
Relay
Output 3
Relay
Output 4
Active/Passive Sensor Jumpers
(All jumpers set to Passive.)
Note:
In 120 VAC applications, L1 must be
the Hot lead and L2 must be the
Neutral/Common lead.
FIG:sys450_app_3stg_bolr