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Circon - 200 Series  

UHC-203 - Unitary HVAC Controller; UHC-203 P - Programmable Unitary HVAC Controller

Secondary Control Units
UHC-203 and UHC-203 P
Date Last Saved: 1/26/2004 10:55:32 AM

Product Name(s): UHC-203 - Unitary HVAC Controller; UHC-203 P - Programmable Unitary HVAC Controller
Product Description: The UHC-203 is a 14-point, LONWORKS compatible, application-specific unitary equipment HVAC controller. The UHC-203_P is a 14-point, LONWORKS compatible, programmable unitary equipment and small AHU controller
Product Application(s): UHC-203: 2-stage heat/cool rooftop A/C units Dual-damper VAV box Multi-stage boilers VAV terminal units Discrete on/off type devices UHC-203_P: (fully programmable) Small AHUs and roof top units Boilers Heat pumps
Point Quantity Characteristics
Analog Input (AI): 5 (4) - 1000 ohm RTD
(1) - 0 to 15Vdc
Digital Input (DI): 3 Dry contact
Universal Input (AI or DI):
Analog Output (AO):
Digital Output (DO): 6 Form C relay (2 Amp @ 24 Vac)
Universal Output (UO):
A/D Converter Resolution
8 bit
10 bit
12 bit
16 bit
D/A Converter Resolution
6 bit
8 bit
10 bit
No Analog Output
Other 12 bit
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?
Integral Damper Actuator?
Can controller accept occupant override from thermostat?
Can controller accept occupancy sensor input?
Expander Boards
Network Ports, Protocol(s), and Speed(s) Supported
(Note: See 'Architecture' for network details)
(1) - LonTalk with Echelon Free Topology Transceiver (FFT-10) to LON @ 78 Kbps
External Communication Ports, Speeds and Access Devices None
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
Laptop/PC via direct connection to LON network
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 None. But see CLI-200 local display panel in Architecture form (permits viewing and changing parameters via direct connection to LON network).
Zone Interface Hardware
Zone-Mounted touchpad (thermostat or stand-alone display)
HID (proprietary device)
PDA (3rd party HID, with software)
Other Not applicable
*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
Laptop/PC via direct connection to LON network
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) Neuron 3150 chip
Clock Type
Powered, battery-backed
Battery powered
Powered, no battery backing
Clock Synchronization One controller is defined during system configuration/setup as the reference timepiece that others synchronize to
Volatile Memory (RAM) Capacity Information not provided
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? Yes
Battery Type(s) Lithium battery
Battery Life 3 years
Backup Battery Operating Time Lithium battery will provide 1 year backup power to maintain data - not operate controller.
Non-Volatile Memory Capacity (EEPROM/Flash)* Information not proivded
Non-Volatile Memory Uses
Data / Trends / Alarms / Calculation Storage
Configuration / Parameter Storage (setpoints, parameters, user settings, schedules, etc.)
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? Yes up to 10 individual trends can be configured (10 different sets of trend values)
How many total trend values can be stored? Approx 1000 values allocated over the configured trends
What is the controllers role in trending? Trend data is pulled from controller by OW
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? If controller trend data buffer fills before being called by archive workstation, old data is overwritten.
Programming Method(s) UHC-203: not programmable - configurable only. User can select from several personality applications which are downloaded and configured from OW.

UHC-203_P: Line code programming
Resident vs Non-Resident Program Execution All program execution is controller resident
Resident/Supervisory. This controller supervises the scheduling of other controllers. UHC-203 & UHC-203 P
Resident/Stand Alone. This controller contains its own schedule. UHC-203 & UHC-203 P
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 UHC-203 P
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 UHC-203
Specific Pre-Programmed Algorithms Available
None (custom programming only) UHC-203
None (not applicable)
Optimal Start/Optimal Stop UHC-203 P
Peak Demand Limiting/Load Shedding
Economizer (enthalpy, dry-bulb, CO2, modulating/2-position, etc.)
Additional Energy Management functions are resident at SI
Additional Programming Functions
DDC Loops (P, PI, PID) PID
Automatic PID Tuning Feature No
Automatical-Dial Alarm Support No- See SMC-202 in Architecture form
Does controller perform multiple retries and buffer/store alarm until connection is made? No auto-dial alarm
Are multiple destinations possible? No auto-dial alarm
Upon controller power loss or hardware failure:
Are network communications affected? No
Is loss recognized on/by the network and alarm reported? Yes - By SMC202. Also reports when controller is restored
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
Upon restoration of power does the controller:
Auto-reboot without operator intervention? Yes
Automatically reset/synchronize the clock? Yes
Update all monitored functions? Yes
Generate an alarm if backup battery is dead? No
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.)
Does network automatically reconfigure upon restoration? No
Does network store 'loss of communications' alarm with time of event? No
Additional Information (optional)
Self Test Diagnostics
Does controller have internal self-test diagnostics to check:
Processor failure? No
Internal hardware failure? No
Open/shortened sensor? No
Control Enclosure Optional
Power Supply Required
Voltage 24 Vac, 50-60Hz
VA 0.4 Amp
Surge Protection No
Underwriters Laboratories UL 916 certification for energy management equipment
FCC FCC Part 15, Subpart J, Level A
CE No, Other - CSA 22.2 #205-M1983, #950-M89
LonMark Certified
No - but LonWorks compatible
Information not provided
BACnet (BTL) Certified
Not submitted for testing
Information not provided