Aerco Acs Modbus Control And Monitoring; Modbus Remote Setpoint Control And Monitoring; Ems Or Bas Set-Up As Master To Bcm Controller Slaves; Multiple Modulex Boiler Heating Mode - Using Acs - Watts AERCO EXT Installation, Operation & Maintenance Manual

Ufly Controller and BCM for Modulex EXT
CHAPTER 6: BOILER COMMUNICATIONS MODULE (BCM)

6.8.2 AERCO ACS Modbus Control and Monitoring

The BCM's modulation output can be controlled by writing to its requested modulation level
register (Standard Holding Register or Control Register #1). It will ramp up the boiler based on
the settings in the Standard Holding Register or Setting Register 3000 to 3015. The default
maximum setpoint temperature limit is 180°F as shown in register 3015. This value should not
be increased, if possible. The default timeout interval is 30 seconds as shown in register 3011.

6.8.3 Modbus Remote Setpoint Control and Monitoring

To send a setpoint temperature to the BCM and have it control the boiler based on its internal
settings, 2 registers need to be programmed:
•
The desired setpoint should be written to the Requested Setpoint (Address 1004) in the
Standard holding Registers or Control Registers. This value should be written at least 3
times within the Communication Timeout time.
•
Write 100 to Address 1. This address sets the maximum firing rate that the boiler can go
to as needed to satisfy the Requested Setpoint entered in above Address 1004.
NOTE: If power is lost all Control Register settings return to default. Be sure to read regularly
and refresh if necessary. The changes to the Settings Registers are stored during power-down.

6.8.4 EMS or BAS Set-Up as Master to BCM Controller Slaves

Refer to set-up instructions in the manufacturer's equipment manual for the Energy Management
System (EMS) or Building Automation System (BAS) being used as the controlling Master.
6.9 Multiple Modulex Boiler Heating Mode – Using Acs
Multiple Modulex boiler plants are the ultimate energy conversion for building space heating. By
modulating input at extremely high combustion efficiency, there is no wasted energy from
overshoot. A multiple Modulex boiler plant offers inherent standby protection and ease of
installation along with longevity.
In a boiler plant with two or more boilers, the use of an AERCO Control System (ACS) is
recommended for maximum efficiency and flexibility of operator control. The ACS has the
capability of controlling up to 32 boilers as well as auxiliary equipment. The ACS system has an
Internal Plant Start adjustment that can be set from 32°F to 100°F outdoor air temperature.
When the boiler plant is activated, the system pump should be started simultaneously. This can
be controlled from outside the ACS, but boilers that fire with no flow will trip out on internal high
temperature limit controls.
The following example briefly explains the operational sequence for a boiler plant consisting of
multiple Modulex Boilers controlled by ACS.
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