QCA-0811 Application Controller

COSYS Building Controls


Our COSYS Application and System Controls work along with our enterprise software platform OspreyFMS to provide a meaningful context.

The QCA-0811 is a fully programmable, Native BACnet® Advanced Application Controller that either communicates on Twisted-Pair Ethernet 10-BaseT using BACnet IP and BACnet over Ethernet (optional) or an RS-485 LAN using the BACnet  S/TP protocol. It is designed for a wide-range of applications that have medium local I/O requirements. 


  • Fully programmable in GCL+
  • Super Capacitor for real-time clock and SRAM backup which requires no maintenance (PoE option)
  • Supports 8 network sensors on LINKnet for room sensing and control
  • Actuator power terminal (24 VAC) for each analog output (can be powered internally or from an auxiliary transformer)
  • Firmware upgrade and database load/save over the network
  • Optional field upgrade to Modbus® RTU with hardware key
  • Service port
  • Screw or DIN rail mountable
  • LED indicator for each output, power, CPU and SCAN status


The QCA-0811 is suitable for controlling various packaged units and equipment with medium I/O requirements such as multiple-room reheat valves or small air handling units, boilers and chillers. The fully programmable QCA-0811 can be tailored to specific applications by creating and modifying BACnet objects and GCL+ programs.


BACnet Device Profile
BACnet Advanced Application Controller (B-AAC)

11 Universal Inputs (10-bit) supporting:
0-5 VDC
0-10 VDC
10 kΩ Thermistor
Dry Contact (using 10 kΩ Thermistor jumper setting)
4-20 mA

8 Analog Outputs (0-10 VDC)

Device Addressing
Set via DIP switches and jumpers, or software setup

Removable screw-type terminal connectors

Wiring Class
Class 2 / SELV

24 VAC 50/60 Hz @ 20 VA

16-bit processor
1 MB flash memory
127 KB SRAM memory for database

QCA-811 (PoE)
16-bit processor
2 MB flash memory
319 KB SRAM memory for database
Real-time clock
Super Capacitor for 72-hour backup of realtime clock and SRAM

Communications Ports
Main LAN
Ethernet (10-BaseT)
BACnet IP, BACnet over Ethernet (PoE only)
RS-485 NET1
BACnet MS/TP up to 76800 bps, max 99 devices per port
RS-485 NET2
LINKnet up to 76800 bps, max 12 devices on LINKnet with no more than 2 DFM devices
Optional Modbus up to 38400 bps, max 5 devices

32° to 131°F (0° to 55°C)
10 to 90% RH (non-condensing)

10⅜ x 4¼ x 1 1516 in. (26.2 x 10.7 x 4.9 cm) with housing

0.944 lb. (428 g) with housing



Order the QCA-811 with the desired options according to the following product numbers:

QCA-811 Application Controller 11 inputs,  8 BOs, MS/TP

QCA-811 (PoE) Application Controller 11 inputs, 8 BOs, Ethernet

Note: When using Ethernet, MS/TP protocol is not available (RS-485 ports can be used for LINKnet and/or special interfaces only).