Setting The Setpoint; Remote Setpoint Modes - Watts AERCO Benchmark OMM-0121 Operation And Maintenance Manual

Benchmark 750-3000 Boiler Operation & Maintenance Manual
SECTION 3 – MODES OF OPERATION

3.3.1 Setting the Setpoint

The setpoint temperature of the unit is adjustable from 40°F to 240°F (4.4°C to 115.6°C). To set
the unit for operation in the CONSTANT SETPOINT mode, you must set menu items Internal
Setpt and Boiler Mode in the Configuration menu as follows:
TABLE 3-1: Constant Setpoint Mode Settings
MENU OPTION SETTING
Select desired setpoint using ▲ and ▼ arrow
Internal Setpt
keys (40°F to 240°F, 4.4°C to 115.6°C)
Boiler Mode Constant Setpoint
See Section 2.3: C-More Controller Menus for detailed instructions on changing menu options.

3.4 REMOTE SETPOINT MODES

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 within the following ranges:
•
4-20 mA/1-5 VDC
•
0-20 mA/0-5 VDC
The factory default setting for the REMOTE SETPOINT mode is 4 - 20 mA/1 - 5 VDC. With this
setting, 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 a 40°F (4.4°C) setpoint while a 20 mA /5V signal is
equal to a 240°F (115.6°C) setpoint. When a 0 to 20 mA/0 to 5 VDC signal is used, 0 mA is
equal to a 40°F (4.4°C) setpoint.
In addition to the current and voltage signals described above, the REMOTE SETPOINT mode
can also driven by a RS-485 Modbus Network signal from an EMS or BAS.
The REMOTE SETPOINT modes 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 C-More Controller. Contact your
local AERCO representative for details.
In order to enable the REMOTE SETPOINT mode, you must set menu items Boiler Mode and
Remote Signal in the Configuration menu as follows:
TABLE 3-2: Remote Setpoint Mode Settings
MENU OPTION SETTING
Boiler Mode Remote Setpoint
Remote Signal 4-20mA/1-5V, 0-20mA/0-5V, or Network
Refer to section 2.3: C-More Controller Menus for detailed instructions on changing menu
options.
OMM-0122_D • GF-206 • 5/9/2019 Technical Support • (800) 526-0288 • Mon-Fri, 8 am - 5 pm EST Page 33 of 164