Benchmark with Edge [I]: Operation-Maintenance Manual
SECTION 6
– MODES OF OPERATION
OMM-0145_A99
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6.2 CONSTANT SETPOINT MODE
The
Constant Setpoint
mode (the default) is used when a fixed header temperature is desired.
Common uses of this mode of operation include water source heat pump loops, and indirect
heat exchangers for potable hot water systems or processes.
No external sensors are required to operate in this mode. While it is necessary to set the
desired setpoint temperature, it is not necessary to change any other temperature-related
functions. The unit is factory preset with settings that work well in most applications. Prior to
changing any temperature-related parameters, other than the setpoint, it is suggested that an
AERCO representative be contacted.
The setpoint temperature of the unit is adjustable from 40°F to 245°F (4.4°C to 118.3°C).
To set the unit to
Constant Setpoint
mode:
Constant Setpoint Mode Setup Instructions
1. Go to:
Main Menu
→
Advanced Setup
→
Unit
→
Application Configuration
.
2. Press
SH Operating Mode
and choose
Constant Setpt
.
3. Press
SH Setpoint
and choose the desired setpoint.
6.3 REMOTE SETPOINT MODE
The unit’s setpoint can be remotely controlled by an Energy Management System (EMS) or
Building Automation System (BAS). The
Remote Setpoint
can be driven by a current or voltage
signal.
NOTE:
See Section 2.11.5:
Analog In
in the
Benchmark 750-6000 with Edge [i]: Install-Startup Manual
(OMM-0144, GF-217) for field wiring instructions.
When using the
Remote Setpoint
mode default setting,
4 - 20 mA/1 - 5 VDC
, a 4 to 20 mA/1 to
5 VDC signal, sent by an EMS or BAS, is used to change the unit's setpoint. The
4 mA/1V
signal is equal to Setpoint Low Limit, while a
20 mA /5V
signal is equal to a Setpoint High Limit
setpoint. When a 0 to
20 mA/0 to 5 VDC
signal is used,
0 mA
is equal to Setpoint Low Limit.
In addition to the current and voltage signals described above, the
Remote Setpoint
mode can
also be driven by a RS-485 Modbus Network signal from an EMS or BAS.
The
Remote Setpoint
mode of operation can be used to drive single as well as multiple units.
NOTE:
If a voltage, rather than current signal is used to control the remote setpoint, a DIP switch
adjustment must be made on the PMC Board located in the Edge [i] Controller. Contact your
local AERCO representative for details.