QCA-1633 / QCA-1633E 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-1633 is a fully programmable, Native BACnet® Advanced Application Controller that communicates on Twisted-Pair Ethernet 10-BaseT using BACnet IP and BACnet over Ethernet (QCA-1633E), or on an RS-485 LAN using the BACnet MS/TP protocol (QCA-1633). It is designed for a wide-range of applications that have small local I/O requirements.


  • Fully programmable
  • Super Capacitor for real-time clock and SRAM backup (requires no maintenance) QCA-1633E
  • Supports 6 BACstat network sensors for room sensing and control or 2 Delta Field Modules for I/O expansion
  • Actuator power terminal (24 VAC) for each analog output (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-1633 is suitable for controlling various packaged units and equipment with small I/O requirements such as fan coil units, unit ventilators, heat pumps, and small boilers or chillers.
The fully programmable QCA-1633 can be tailored to specific applications by creating and modifying BACnet objects and GCL+ programs.


BACnet Device Profile
BACnet Advanced Application Controller (B-AAC)
6 Universal Inputs (10-bit), jumper configurable for:
0-5 VDC
0-10 VDC
10 kΩ Thermistor
Dry Contact (using 10k Ω Thermistor jumper setting)
4-20 mA
3 Binary TRIAC Outputs
24 VAC @ 0.5 A max per output
Leakage Current 100μA, min current 25 mA
Jumper configured for internal or external power
2 Analog Outputs
0-10 VDC @ 20 mA max per output
Software configurable as binary or analog
1 Universal Output
Configurable as either 0-10 V or 24 VDC FET
Device Addressing
Set via DIP switch and jumpers, or software setup
Removable screw-type terminal connectors
Wiring Class
Class 2 / SELV
24 VAC 50/60 Hz @ 50 VA with fully-loaded binary outputs
Power (UL 864)
24 VAC 50/60 Hz @ 12 VA, 50 VA with fully loaded binary outputs
(non-Ethernet version)
16-bit processor
1 MB Flash memory
128 KB SRAM memory for database
(Ethernet version)
16-bit processor
2 MB Flash memory
319 KB SRAM memory for database
Real-time clock
Super Capacitor for 72-hour backup of real-time clock and SRAM
Communications Ports
Main LAN
Ethernet (10-BaseT)
BACnet IP, BACnet over Ethernet
RS-485 NET1
BACnet MS/TP up to 76800 bps, max 99 devices per port
RS-485 NET2
Up to 76800 bps, max 12 devices 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)
8½ x 4¼ x 1 1516 in. (21.8 x 10.7 x 4.9 cm) with housing
0.80 lb. (360 g) with housing
C-UL Listed
UL 916 Listed
BTL Listed
UL 864 Listed for UL 864 product numbers


Order the QCA-1633 with the desired options according to the following product numbers:

QCA-1633 Application Controller 6 inputs, 3 AOs, 3 BOs

QCA-1633 (PoE) Application Controller 6 inputs, 3 AOs, 3 BOs, Ethernet