Aerco BOILER MANAGEMENT SYSTEM II 5R5-384, Installation, Operation & Maintenance Instructions Manual

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GENERAL INFORMATION
1-3
Retention of Menu Option Settings
By using non-volatile memory, the BMS II retains program and menu settings during shut-down or when
input AC power is interrupted. Settings can be retained for more than 2 years.
Application Flexibility
Four different configuration options can be selected to match the needs of any closed-loop system. These
configurations are: Outdoor Reset, Constant Setpoint, Remote Setpoint via a 4-20 Ma input and Remote
Setpoint via Modbus.
Sequential or Parallel Operation
Boilers can be programmed for either sequential or parallel operation using the BMS II keypad controls. When set
for sequential operation, the boilers are brought on-line one at a time as needed. When set for parallel operation, the
boilers are all brought on-line together at the same firing rate.
Accuracy
Using PID (Proportional Integral Derivative) and Ramp-Up/Ramp-Down Modulation Control Algorithms,
the BMS II provides dynamic responses to all changes in boiler plant operation. Header temperatures, as
well as percentages of boiler input are precisely controlled with virtually no over-shoot or short-cycling of
boiler units. A header temperature accuracy of ±2°F is virtually assured during continuous plant operation.
Bumpless Transfer
When operated sequentially, The BMS II stages boilers on and off at selectable firing rate percentages.
The result is a seamless transition with undetectable room temperature changes. In addition, when in
sequential mode, the BMS II sequences boilers using a first-on, first-off basis, thereby equalizing the
accumulated run time of all boilers in the plant.
The BMS II also continuously monitors the number of Boilers that are available for operation. In the event
of a boiler malfunction, or required servicing, the BMS II automatically compensates for a lack of
response from any unit and brings on the next available boiler to satisfy the demand. This feature
operates in both sequential and parallel modes.
Fault Alarm Surveillance
If an EMS or BAS is not used with the BMS II to monitor faults, a Fault Alarm Relay can be activated
thereby notifying facility managers of faults associated with the BMS II.
BMS II Programming Via RS232 Port.
If desired, the BMS II can be programmed by connecting a Laptop Computer or other terminal emulation
device to the RS232 Port terminals on the BMS II. Detailed set-up instructions and available command
listings are provided in Appendix G. Most settings are also programmable using Modbus.