AERCO BMS II BOILER - Manual (Page 54)

PROGRAMMING BMS II
4-4
6. If the boiler plant contains Modulex Boilers, proceed to the next paragraph (Entering Load Start
Percent).
7. If the boiler plant Does Not contain Modulex Boilers, the BMS II is now fully programmed for operation
in the Outdoor Reset Mode.
Entering Load Start Percent (Required Only for Modulex Installations)
If the boiler plant contains Modulex boilers, the LOAD START PCT option in the Calibration Menu must
be entered. This option should be set 2% below the BLR START LEVEL set in the Configuration Menu.
Proceed as follows:
1. Press the MENU key until CONFIGURATION MENU appears in the display.
2. Scroll through the menu using the
▲ or ▼ arrow key until LOAD START PCT appears in the display
along with the current setting for this option (default = 1%).
3. Refer to Appendix I to determine the appropriate BLR START LEVEL for the Modulex Boiler.
4. Press the CHANGE key to change the displayed value. The display will switch to a reverse video
format.
5. Using the
▲ and ▼ arrow keys, set the LOAD START PCT to 2% below the BLR START LEVEL.
6. Press the ENTER key to store the changed percentage. The reverse video display will revert to the
normal VFD display format.
7. The BMS II is now fully programmed for operation in the Outdoor Reset Mode with Modulex Boilers.
4.3 REMOTE SETPOINT MODE
In order to set up the BMS II to operate in this mode, a Modbus communication line or a 4-to-20 mA input
line with a floating ground from an Energy Management System (EMS) is required. In addition, a BMS
header sensor is required. This mode may be used with or without an outdoor air temperature sensor
installed. Entries in this mode are required for the following menu items:
• FIELD ADJUST MENU
o HEADER SET MODE
o HEADER HIGH LIMIT
o HEADER LOW LIMIT
o REMOTE SIGNAL
• CONFIGURATION MENU
o BOILER OPERATING MODE
o BLR START LEVEL
o BLR STOP LEVEL
• CALIBRATION MENU (Required Only For Modulex Installations)
o LOAD START PCT
The programming set-up instructions for the above menu options are provided in paragraphs which
follow.