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Automated Logic - WebCTRL  

U220; U253; U551

Secondary Control Units
U220, U253, and U551
Date Last Saved: 4/1/2004 11:27:58 AM

Product Name(s): U220; U253; U551
Product Description: U-Line Unitary Controller, part of the WebCTRL system
Product Application(s): U253: unit ventilator and packaged HVAC applications U220: unit heater, unit ventilator, lighting, exhaust fan, and other applications U551: heat pump, fan coil and other applications
Point Quantity Characteristics
Analog Input (AI):
Digital Input (DI):
Universal Input (AI or DI): See below Thermistor
0-5 Vdc

Analog Output (AO): See below 0-10 Vdc
Digital Output (DO): See below Relay, 24 Vac/1 Amp
Universal Output (UO):
Control Unit Model #:AIDIUIDOAOUOOther
U253 5 2 3
U220 2 2 0
U551 5 5 1
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
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? No
Integral Damper Actuator? No
Can controller accept occupant override from thermostat? Yes
Can controller accept occupancy sensor input? Yes
Expander Boards U253 and U551 are compatible with U Line Single air Flow sensor (USF) or U Line Dual air Flow sensor (UDF) for pressure independent VAV applications. Connects directly with cable/connector provided with USF and UDF.
Expansion Device Model #AIDIUIDOAOUOOther
Network Ports, Protocol(s), and Speed(s) Supported
(Note: See 'Architecture' for network details)
(1) BACnet port to BACnet secondary network (MS/TP at 9.6 or 38.4 kbps).
External Communication Ports, Speeds and Access Devices U253 and U551: (1) USB-style port @ 1200 bps for communication with zone thermostat. Zone thermostat can be used for test and balance.
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 Yes
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) Hitachi H8 16 bit
Clock Type
Powered, battery-backed
Battery powered
Powered, no battery backing
Clock Synchronization Timing functions are handled by the UNI/16 or UNI/32
Volatile Memory (RAM) Capacity 2 kb RAM
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) None
Battery Life No battery
Backup Battery Operating Time No battery
Non-Volatile Memory Capacity (EEPROM/Flash)* 60 Kb Flash
Non-Volatile Memory Uses
Data / Trends / Alarms / Calculation Storage
Configuration / Parameter Storage
Control Programming Storage
Controller Operating System
Other Information not provided
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? None - See UNI 16/32
What is the controllers role in trending? None - See UNI 16/32
Can controller be programmed to 'push' data to archive or are trends 'pulled' from controller? Information not provided
When full, does controller automatically send up trend data, overwrite data, or stop logging data? None - See UNI 16/32
Programming Method(s) EIKON graphical block programming is used to define the control logic using "Drag-and-drop" of microblocks and logical connections. A browser and server-based WebCTRL software are used to download the control program into the controller through the UNI 16/32. Programming changes are saved to the server's database. Once the database has been changed, the browser interface is used to download the database into/through the UNI 16/32 to the U-card controller.
Resident vs Non-Resident Program Execution Primary control program is stored in UNI/16 or UNI/32. Flow control, local on/off links, and standalone back-up algorithm are resident in the U-card.
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
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.)
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 - function performed by UNI/16 or UNI/32
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
Upon restoration of power does the controller:
Auto-reboot without operator intervention? Yes
Automatically reset/synchronize the clock? Timing functions are handled by the UNI/16 or UNI/32
Update all monitored functions? Yes
Generate an alarm if backup battery is dead? No backup battery
Upon network or communications failure does controller:
Continue to operate standalone? Yes - U-card uses default control algorithm for stand-alone operation
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.)
No (U-cards separated from UNI revert to default algorithm)
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? No
Others? Additional diagnostics and reporting reside in UNI/16 or UNI/32
Control Enclosure Unit is rated for plenum mounting
Power Supply Required
Voltage 24 Vac +/- 10%, 50-60 Hz
VA 7.5 VA
Surge Protection Surge and transient protection circuitry for power and communications. Optical isolation provided for communication.
Underwriters Laboratories UL 916 PAZX (Energy Management)
FCC Part 15, Sub-Part B, Class A
CE Yes
LonMark Certified
No - but LonWorks compatible
Information not provided
BACnet (BTL) Certified
Not submitted for testing
Information not provided