AERCO BMK 6000 Dual Fuel - Manual (Page 76)

Benchmark 6000 DF Installation, Operation & Maintenance Manual
CHAPTER 5 – MODE OF OPERATION
Page 76 of 219 AERCO International, Inc. • 100 Oritani Dr. • Blauvelt, NY 10913 OMM-0096_0B
03/21/2014
Ph.: 800-526-0288
GF-141
must be observed. The source end of the shield must be connected at the source. When driving
multiple units, each unit’s wiring must conform to the above.
5.4.2 Remote Setpoint Startup
Since this mode of operation is factory preset and the setpoint is being externally controlled, no
startup instructions are necessary. In this mode, the REMOTE LED will light when the external
signal is present.
To operate the unit in the Manual mode, press the AUTO/MAN switch. The REMOTE LED will
go off and the MANUAL LED will light.
To change back to the Remote Setpoint mode, simply press the AUTO/MAN switch. The
REMOTE LED will again light and the MANUAL LED will go off.
5.5 DIRECT DRIVE MODES
The unit’s air/fuel valve position (% open) can be changed by a remote signal which is typically
sent from an Energy Management System (EMS) or from a Building Automation System (BAS).
The Direct Drive mode 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 Direct Drive mode is 4-20 mA/1-5 Vdc. With this setting, a 4 to
20 mA signal, sent by an EMS or BAS is used to change the unit’s valve position from 0% to
100%. A 4 mA/1V signal is equal to a 0% valve position, while a 20 mA /5V signal is equal to a
100% valve position. When a 0-20 mA/0-5 Vdc signal is used, zero is equal to a 0% valve
position.
In addition to the current and voltage signals described above, the Direct Drive mode can also
driven by a RS-485 Modbus Network signal from an EMS or BAS.
When in a Direct Drive mode, the unit is a slave to the EMS or BAS and does not have a role in
temperature control. Direct Drive can be used to drive single, or 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
Control Box Assembly. Refer to Appendix D of the C-More Control Panel
OMM, GF-112, for DIP switch settings, or contact your local AERCO
representative for details.
To enable the Direct Drive Mode, the following menu setting must be made in the Configuration
Menu:
Menu Option Setting
Boiler Mode Direct Drive
Remote Signal 4-20mA/1-5V, 0-20mA/0-
5V, or Network
Refer to section 3.3 for instructions on changing menu options.