The FlexStat™ from KMC® Controls is a (B-AAC) BACnet advanced application controller and sensor in a single package. The BAC-12xxxx, 13xxxx, and 14xxxx digital control series creates a flexible solution to standalone control challenges or BACnet network challenges in commercial and industrial facilities.
Space temperature sensing is standard with the FlexStat. Optional built-in sensors are humidity, CO2, and motion/occupancy. Six inputs for external sensors are also provided. If a remote space temperature sensor is connected to one of the inputs, the FlexStat can be configured to use remote only, average, highest, or lowest reading. The motion sensor has a range of over 30′, and built-in sequences include occupancy standby and occupancy override.
Flexible input and output configurations and built-in or custom programming ensure that a variety of application needs can be met. Such applications include single- and multi-stage packaged, unitary, and split systems (including high SEER/EER variable speed packaged equipment), as well as factory packaged and field-applied economizers, water-source and air-to-air heat pumps, fan coil units, central station air handling units, and similar applications.
In addition, an on-board library of programs permits a single model to be configured for a wide range of HVAC control applications. Thus, a single “one size fits all” FlexStat model can replace multiple competitor models. A single BAC-120163CW, for example, can be configured for any of these application options:
- Air handling unit, with proportional heating and cooling valves, and with optional economizer, dehumidification, and/or fan status
- Fan coil unit, two-pipe or four-pipe, proportional or two-position valves, with optional dehumidification (w/ four -pipe option) and/or fan status
- Heat pump unit, with up to two compressor stages, and with optional auxiliary heat, emergency heat, dehumidification, and/or fan status
- Roof top unit, with up to two H/C stages, and with optional economizer, dehumidification, and/or fan status
FlexStats also provide the capability to customize the standard library of sequences using a KMC programming tool (BACstage or TotalControl). BACnet over MS/TP communication is standard. “E” versions, with an RJ-45 jack, add BACnet over Ethernet, BACnet over IP, and BACnet over IP as Foreign Device (for communication across the Internet).
The FlexStat digital control features English-language menus (no obscure numeric codes) on a 64 x 128 pixel, dot-matrix LCD display with five buttons for data selection and entry. Multiple display options include selectable space temperature display precision, degrees F/C toggle, rotation values, display blanking, hospitality mode, and locked mode. Integral energy management control offers optimum start, dead band heating, and cooling set points. Schedules can be set for the entire week, weekdays, weekends, individual days, and/or holidays; six On/Off and independent heating and cooling set point periods are available per day.
The BAC-13xxxx series digital control, with a built-in CO2 sensor, uses Automatic Background Calibration Logic, a patented self-calibration technique designed to be used in applications where CO2 concentrations will drop to outside ambient conditions (approximately 400 ppm) at least three times in a 14 day period, typically during unoccupied periods. The BAC-13xxxx series, when properly configured, complies with CA Title 24, Section 121(c), as well as sub-paragraph 4.F. The BAC-14xxxx series is designed for zones with continuous occupancy. The BAC-12xxxx series can have a remote CO2 sensor connected to one of the external inputs. All models are available with three levels of Demand Control Ventilation (DCV) sequences when using applications with a modulating economizer option and an internal or external CO2 sensor.
Three levels of password-protected access (user/ operator/administrator) prevent disruption of operation and configuration—plus Hospitality mode and Locked User Interface mode offer additional tamper resistance. All FlexStat models have 72-hour power (capacitor) backup and a real-time clock for network time synchronization or full stand alone operation.