BACnet® Controller

Engineered to exceed the specifications for a wide variety of variable air volume (VAV) applications, the Reliable Controls MACH‑ProAir™ is a fully programmable BACnet Building Controller (B‑BC) with numerous downloadable standard codes and flexible input and output options, all priced to meet a modest budget.

Purchase Products

Product features

Dynamic Database

  • Create up to 160 objects of any supported type in any model of controller.
  • Maximum of 128 objects of a single type.
  • Refer to the Typical Object Configuration table below for memory usage.


  • BACnet MS/TP (EIA-485).

Motor Control

  •  Standard VAV and optimized motor control algorithms stored in firmware.
  • Option to program your own algorithm.
  •  Download numerous standard application codes from the Reliable Controls website.

Engineered Enhancements

  •  Onboard End-of-Line (EOL) switch with LED indication provides easy EOL configuration and visual verification.
  •  Remote addressing and software-selectable inputs allow you to complete detailed configuration over the network.
  •  Robust capacitor-backed SRAM nonvolatile memory preserves trend data on power cycle.
  •  BACnet change of value support provides optimized network sharing.


  •  16,000 bytes of programmable control strategy in a readable, BASIC-like language.
  •  3,200 bytes per program.


  •  Universal ranges.
  •  Software-selectable 0–10 VDC, 4–20 mA, thermistor/dry contact.


  •  Universal ranges.
  •  0–12 VDC or solid-state relay, model dependent.


  • Select standard and custom ranges as well as fixed or program-driven values.


  • Standard P, PI, or PID controllers for closed loop control.

Single-point Trend Logs

  •  Store 128 samples at programmable time intervals.

Multipoint Trend Logs

  • Store up to eight objects in each trend log.
  • Record values as user-defined intervals.
  • Dynamically assigned.

Runtime Report

  •  Totals the on time and records the on/off times of every binary object.
  •  A 50-sample runtime log is automatically enabled for each binary object.

System Groups

  •  Group related points on one display.
  •  80 objects per group.


  • Seven on/off times for each weekday or exception.


  • Designate days of the year as holidays.


  • Up to 128 elements in a one-dimensional array.


  • For creating custom input ranges and program lookup tables.

Custom Units

  •  Eight analog engineering units.
  •  Eight binary engineering units.
  •  Eight multistate units with eight states, 32 characters each.

SMART-Net Port

  • Network up to four SMART-Net devices.

64 Net Ins

  • The maximum number of shares from other devices.

32 Net Outs

  • The maximum number of writes to other devices.


  • 5 years.

Typical Object Configuration
There are physical limitations to the number of inputs, outputs, and SMART-Sensors that can be connected to a MACH-ProAir controller. For other object types, a maximum number of 128 objects of a single type can be created. The total number of objects (including inputs, outputs, and SMART-Sensors) is limited to 160, and is also limited by the onboard memory. The table below details typical databases that fit in all models.

Variables Loops Schedules Calendars Tables* Groups Multipoint Trend** Runtime* Arrays Program SMART-Sensor
64 8 4 2 4 4 10 128 4 16 4

* Runtime Reports and Tables are not counted in the 160 object limit. Inputs and outputs are counted in the 160 object limit.
** Trends are configured to store 128 samples.

RoHS 3 Certified BTL Listed Device

Technical specifications

Processor and Memory

  • 66 MHz high-performance 32-bit embedded microcontroller with onboard Flash memory.
  • Controller database stored in robust nonvolatile memory. Values and log data are stored in 3-day capacitor-backed memory.
  • Easily update operating system firmware at any time over the network.

Supply Voltages

  • 24 VAC ±10% 32 VA maximum, 50/60 Hz.
  • 24 VDC ±10% 12 W maximum.

Communication Options

  • One EIA-485 (RS-485) port that supports a baud rate up to 76.8 kbps with auto-baud detection.
  • Two SMART-Net ports, one RJ-11 and one 4-wire terminal block, that support up to four devices.

Universal Inputs

  • 12-bit A/D converter.
  • Use software to select 0-10 VDC, 4-20 mA, thermistor/dry-contact.
  • Impedance:
    • 3 MΩ on 0-10 VDC range.
    • 250 Ω on 4-20 mA range.
    • 20 kΩ on thermistor range.
  • Pulse counting up to 40 Hz. Supports flow meters.
  • 24 VAC overvoltage protection.

Velocity Sensor

  • ±0-500 Pa (0"-2" WC).
  • Maximum zero point accuracy 0.2 Pa (0.0008" WC).
  • Resolution: 0.122 Pa (0.0005" WC).
  • Span accuracy 3% of reading.

Flow Pickup

  • 5.2 mm OD barbed fittings.
  • Suitable for 1/4" standard pneumatic control tubing.

Universal Outputs

  • 10-bit D/A converter.
  • Analog: 0-12 VDC.
  • Binary: Software configurable between 0–12 VDC.
  • Output power: 75 mA at 12 VDC.
  • 24 VAC overvoltage and short protection.

Solid-State Relay Outputs

  • Switch 24 VAC/VDC.
  • 500 mA max.

Wiring Terminal

  • 16–28 AWG.
  • Stranded or solid core.
  • Copper conductors only.


  • Torque 5 Nm (45 in-lb).
  • Brushless D.C.
  • Compatible with 3/8" to 1/2" damper blade shaft.
  • Maximum throw of 95 degrees.
  • Actuator speed: 1 degree per second.


  • Base model:

    19.9 cm L x 10.1 cm W x 7.3 cm H

    (7 13/16" L x 3 15/16" W x 2 7/8" H).

  • With actuator:

    22.7 cm L x 10.1 cm W x 7.7 cm H

    (8 15/16" L x 3 15/16" W x 3" H).

  • With MPA-C:
    22.7 cm L x 15 cm W x 7.7 cm H

    (8 15/16" L x 5 7/8" W x 3" H).

Mount Hardware Included

  • #8 screw.


  • 0.7 kg (1.8 lb).

Ambient Limits

  • Operating: 0°C to 50°C
    (32°F to 122°F).
  • Shipping: -40°C to 60°C
    (-40°F to 140°F).
  • Humidity: 10%–90% RH noncondensing.


  • ABS.
  • UL 94-5V.



SMART–Net connection

VAV with reheat coil

Dual–duct VAV