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Terminal Box Controller; Fan Coil Unit Controller; Heat Pump Controller

Secondary Control Units
BACnet Terminal Equipment Controller (BTEC)
Date Last Saved: 12/13/2007 8:59:48 AM

Product Name(s): Terminal Box Controller; Fan Coil Unit Controller; Heat Pump Controller
Product Description: The BTEC controllers can operate stand-alone or can be networked to perform HVAC control, monitoring, and energy management functions. The BTEC controllers are designed to communicate with the Siemens Building Technologies APOGEE System via BACnet MS/TP.
Product Application(s): Terminal Box Controller - designed for pressure independent VAV air terminal applications with or without reheat options. Fan Coil Unit Controller Heat Pump Controller - designed for water source heat pumps with ventilation of mixed air control and air to air heat pumps with ventilation and mixed air control. Multiple stage configuration.
Point Quantity Characteristics
Analog Input (AI): See Below Room Temperature Sensor
Setpoint Adjustment
Auxillary Temperature Sensor
Velocity Sensor (VAV controller only)
Digital Input (DI): See Below Dry contacts
Universal Input (AI or DI): N.A.
Analog Output (AO): N.A.
Digital Output (DO): See Below 24 Vac optically isolated Solid State switches
Universal Output (UO):
Control Unit Model #:AIDIUIDOAOUOOther
Terminal Box Controller 550-788A 4 2 6
Fan Coil Unit Controller 550-789A 3 2 6
Heat Pump Controller 550-790A 3 2 8
A/D Converter Resolution
8 bit
10 bit Air Velocity Sensor (actually a frequency counter)
12 bit
16 bit
D/A Converter Resolution
6 bit
8 bit
10 bit
No Analog Output
HOA switches provided on each output?
Note: These are also available as an add-on from 3rd party vendors.
Both AO and DO
DO Only
Indicating status LED on each output?
AO and DO
AO Only
DO Only
Integral Flow Sensor? VAV controller has integral velocity sensor.
Integral Damper Actuator? No.
Can controller accept occupant override from thermostat? Yes, setpoint adjustment is an optional analog input.
Can controller accept occupancy sensor input? Yes, occupancy sensor can be input to one of the DI dry contacts.
Expander Boards None.
Network Ports, Protocol(s), and Speed(s) Supported
(Note: See 'Architecture' for network details)
(1) EIA-485 port for BACnet MS/TP @ 9.6 to 38.4 kbps
External Communication Ports, Speeds and Access Devices (1) - EIA-232 laptop/PC communication ports with RJ-11 jack @ up to 38.4 kbps
To: Zone-based port on thermostat (optional)
Additional Information (Optional)
Network Accessing Capabilities via Controller
Access controller only
Access controller plus additional controllers on network segment / LAN
Access all controllers on system
No access available on this controller
Controller Access Devices
Local Display Panel (controller-mounted)
Local Display Panel (zone-mounted)
Handheld Interface Device (proprietary device)
PDA (3rd-Party HID)
Zone-Based port (details below)
Zone-Based Interface Access Optional thermostats available with port to access controller via laptop.
Zone Interface Hardware
Zone-Mounted touchpad (thermostat or stand-alone display)
HID (proprietary device)
PDA (3rd party HID, with software)
*Note: This section covers the capabilities for accessing the controller or other parts of the network from the controller (i.e. 'bottom-up').
Standard access functionality is covered in the Architecture and Software sections.
**Does NOT include front-end OI functions. See vendor for specific functions available.
Functions Available Through Field Interface**:View ParamsChange ParamsChange
O&M SupportTAB/Cx Support
Local Display Panel (controller-mounted)
Local Display Panel (zone-mounted)
Handheld Interface Device (proprietary device)
PDA (3rd-Party HID)
Zone-Based port (details below)
Microprocessor(s) Motorola 68HS12
Clock Type
Powered, battery-backed
Battery powered
Powered, no battery backing
Clock Synchronization N.A.
Volatile Memory (RAM) Capacity 12 kb
Volatile Memory (RAM) Uses
RAM use unrestricted
RAM use restricted as shown below
Information Not Provided
Program Execution / Calculation storage
Data / Trends / Alarms storage
Configuration / Parameter storage
Control Programming storage
Is Volatile Memory Supported By Battery? No
Battery Type(s) N.A.
Battery Life N.A.
Backup Battery Operating Time N.A.
Non-Volatile Memory Capacity (EEPROM/Flash)* 256 kb EEPROM
Non-Volatile Memory Uses
Data / Trends / Alarms / Calculation Storage
Configuration / Parameter Storage
Control Programming Storage
Controller Operating System
Additional Information
* Items in NV memory are not lost upon power or battery failure. Other types of NV memory such as EPROM, NOVROM, etc. do not directly impact system performance.
Can trend data be stored in this controller? No
How many total trend values can be stored? N.A.
What is the controllers role in trending? None. Trend point data is called by the SI and stored at the OWS.
Can controller be programmed to 'push' data to archive or are trends 'pulled' from controller?
When full, does controller automatically send up trend data, overwrite data, or stop logging data? N.A.
Programming Method(s) Pre-existing programs ('applications') are configured using Voyager. Voyager is a Windoows-based program that allows users to communicate directly with any Terminal Equipment Controller to view, modify, or command point information. Initially, secondary control units must be configured locally, then address is kept in EEPROM allowing complete access and reconfiguration capability from workstation or portable terminals.
Resident vs Non-Resident Program Execution Resident programming will allow control to function as stand-alone. Primary controllers or supervisory interface devices manage scheduling, trending, global control, and communication functions.
Resident/Supervisory. This controller supervises the scheduling of other controllers.
Resident/Stand Alone. This controller contains its own schedule.
Non-Resident. This controller is dependent upon another controller for its schedule.
None. This controller has no scheduling features.
Resident Energy Management
Energy management algorithms for this controller can be custom programmed
Pre-programmed/built-in algorithms available, and are fully editable using custom programming
Pre-Programmed/built-in with limited editing via template-based programming
Controller is not typically used for energy management functions
Others See 'Additional Programming Functions' below
Specific Pre-Programmed Algorithms Available
None (custom programming only)
None (not applicable)
Optimal Start/Optimal Stop
Peak Demand Limiting/Load Shedding
Economizer (enthalpy, dry-bulb, CO2, modulating/2-position, etc.)
Other See 'Additional Programming Functions' below
Additional Energy Management functions are resident at SI
Additional Programming Functions A wide variety of configurable energy management features are available on the various BTECs (dependent on model and application).
DDC Loops (P, PI, PID) PID
Automatic PID Tuning Feature No
Automatical-Dial Alarm Support No
Does controller perform multiple retries and buffer/store alarm until connection is made? No
Are multiple destinations possible? No
Upon controller power loss or hardware failure:
Are network communications affected? No
Is loss recognized on/by the network and alarm reported? Yes
DO and AO response?
Outputs fail to a user pre-specified position
Outputs fail to a normal (unpowered) position
Outputs fail to last position
Volatile memory functions?
Retained for life of backup battery
Other Controller has no volatile memory
Upon restoration of power does the controller:
Auto-reboot without operator intervention? Yes.
Automatically reset/synchronize the clock? No clock
Update all monitored functions? Yes - update received from field panel - MBC/RBC, MEC, or FLNC (SI)
Generate an alarm if backup battery is dead? N.A.
Upon network or communications failure does controller:
Continue to operate standalone? Yes
Operate with last global settings or user-specified value? N.A.
Do broken network segments continue to communicate within the remaining segment?
(Note: May depend on proper termination of segments for higher speed networks.)
Yes, if configured as masters.
Does network automatically reconfigure upon restoration? Yes
Does network store 'loss of communications' alarm with time of event? Yes
Additional Information (optional)
Self Test Diagnostics
Does controller have internal self-test diagnostics to check:
Processor failure? Yes
Internal hardware failure? Yes
Open/shortened sensor? Yes
Control Enclosure Controller is housed in a plastic case.
Power Supply Required
Voltage 19.2 to 27.6 Vac at 50/60 Hz
VA 10 VA (plus 12 VA per DO)
Surge Protection Yes.
Underwriters Laboratories UL 916, PAZX
cUL C22.2 No. 205-M1983, PAZX7
FCC 47 CFR Part 15
CE Information not provided.
LonMark Certified
No - but LonWorks compatible
Information not provided
BACnet (BTL) Certified
Not submitted for testing
Information not provided