BMC Overview

BMC and BMC-6X Installation and Operation Manual

SEQUENCES UP TO 4 FULLY MODULATING STAGES.

The BMC is the perfect control whenever multiple fully modulating stages are required for hydronic heating applications. The BMC controls the on/off and the modulation of each stage to maintain precise system set point control.

PID TYPE LOGIC

The BMC’s control algorithms allow it to look at the rate of change in the system. If the system temperature is changing quickly, the BMC will react quickly to adjust the modulating stages’output. If the system temperature changes slowly, the BMC will make slow and gradual output adjustments. Therefore, the BMC adapts to speciﬁc system requirements and minimizes ﬂuctuations around the set point.

CONTROLS 0-5 V, 0-10 V, 1-5V, 2-10V, OR 4-20 MA MODULATING MOTORS

The BMC is designed to accurately control the output from 0 to 100% of modulation for each of these different types of motors. One BMC can even control a variety of the above different motors.

ONLY ONE SENSOR

When Set Point sensor type is selected, the BMC requires only one sensor located in the common output header of all stages. However, when Reset is selected, an additional Outdoor Sensor is required for Outdoor Reset Ratio input.

DIGITAL DISPLAY OF ALL SYSTEM SETTINGS

The BMC’s alphanumeric digital display names each system parameter in simple English and shows its precise value. The easy to follow menu system allows users to quickly make changes to any system setting without having to learn any specialized codes or keyboard commands.

AUTOMATIC ROTATION AMONG STAGES

Rotating the ﬁrst stage to be activated on a call for output promotes even wear on each stage. The BMC has three modes of rotation: Manual, Last On, or Time. The Time rotates the lead stage every selected time period from every hour to every 60 days.

OUTDOOR RESET

The BMC has a hydronic outdoor temperature reset function. This allows the BMC to change the set point based on outdoor temperature. Furthermore, additional settings have been added to ﬁne tune this operation, like Offset, Minimum, and Maximum Water Temperature and night setback schedule.

STANDBY BOILERS

Each of the BMC stages can be conﬁgured as a Standby boiler with an adjustable Standby delay. A boiler can be used as a backup during extended large demand periods.

SYSTEM OUTPUT

In Set Point mode, this output can be used to activate a system pump, combustion air damper, or perform any other function that is required when any stage is active. In Outdoor Reset mode, the System Output will activate whenever the outdoor temperature is below the Outdoor Cutoff setting. A System Prove input checks the status of components activated by the System output before stages can be activated.

STAGING (NORMAL) OR PARALLEL MODULATION

The BMC can stage boilers as needed. That will allow it to increase the modulation on the lead boiler. When the lead boiler reaches its modulation start point adjustment and does not satisfy the load, the BMC will start the next boiler and so on... Moreover, the BMC allows for a parallel mode that can modulate several boilers together as a one large boiler. This mode is useful for boilers with lower water content, which are usually more efﬁcient at lower ﬁring points.

ADD UP TO 16 BOILER STAGE (OPTIONAL)

As a stand-alone, the BMC is designed to control four modulating boilers. However, it has the capability of expanding its control to two extension panels each with six boiler stages. Thus, the BMC can control a total of up to 16 boiler stages.