DDC Online direct digital controls
Automated Logic - WebCTRL  

ZN220; ZN253; ZN551

Primary Control Unit
ZN Line
Date Last Saved: 3/29/2004 4:09:46 PM

Product Name(s): ZN220; ZN253; ZN551
Product Description: Stand-alone Zone Controllers
Product Application(s): The ZN253 and ZN551 are zone controllers for VAV, heat pump, unit ventilator and other packaged HVAC applications. The ZN220 is suitable for a variety of applications including fan coil units, lighting, and exhaust fan control.
Point Quantity Characteristics
Analog Input (AI): N.A.
Digital Input (DI): N.A.
Universal Input (AI or DI): See Below dry contact
Type 2 thermistors
0-5 Vdc
Analog Output (AO): See Below 0-10 Vdc
Digital Output (DO): See Below Relay contact (1A max @ 24 Vac)configured normally open
Universal Output (UO): N.A.
Other: Rnet port supports Automated Logic’s line of RS room sensors and provides local access to the system.
Control Unit Model #:AIDIUIDOAOUOOther
ZN551 5 5 1
ZN253 5 2 3
ZN220 2 2 0
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 (dry contact or 0-5Vdc)
Expander Boards ZN551 and ZN253 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) EIA-485 BACnet port to primary BACnet network (ARCNET at 156 kbps or MS/TP at 9.6, 19.2, 38.4, or 76.8 kbps)
External Communication Ports, Speeds and Access Devices (1) Local access port for system start-up and troubleshooting
(1) Rnet port for RS room sensors
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 Laptop can be connected to the RSPro and RSBasic sensor for full system access.
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) 16-bit microprocessor with ARCNET communication co-processor.
Clock Type
Powered, battery-backed
Battery powered
Powered, no battery backing
Clock Synchronization Time synchronization occurs periodically through broadcasts from the WebCTRL server, and from the BACnet Router on each network segment.
Volatile Memory (RAM) Capacity Module only contains non-volatile and flash memory.
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
Others N.A.
Is Volatile Memory Supported By Battery? N.A.
Battery Type(s) N.A.
Battery Life N.A.
Backup Battery Operating Time N.A.
Non-Volatile Memory Capacity (EEPROM/Flash)* 512 KByte non-volatile battery-backed RAM, 1 MByte Flash memory, 16-bit memory bus
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? Yes
How many total trend values can be stored? The user has complete control over how trend memory is used, including how many points are trended, how often the trend samples are taken, how many samples are stored in the module, and whether or not the trend data will be backed up to a historical database on the server.
What is the controllers role in trending? Controller samples data either at time intervals or based on change of value
Can controller be programmed to 'push' data to archive or are trends 'pulled' from controller? Controller can be programmed to push data to archive, or data can be dynamically pulled from the controller for display
When full, does controller automatically send up trend data, overwrite data, or stop logging data? User defines whether controller should stop when full or begin overwriting oldest data
Programming Method(s) ZN Line controllers are fully graphically programmable using the Eikon graphical programming software.
Resident vs Non-Resident Program Execution All graphical programs reside in the controller.
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 A library of pre-engineered control routines provides solutions for most zone control applications. Custom programs can be easily written in EIKON® using ALC’s graphic programming language.
DDC Loops (P, PI, PID) Available through custom Eikon graphical programming
Automatic PID Tuning Feature No
Automatical-Dial Alarm Support Yes
Does controller perform multiple retries and buffer/store alarm until connection is made? Yes
Are multiple destinations possible? Yes
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 shelf life 10 years with 10,000 hours of continuous operation
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? Yes
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? 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?
Control Enclosure Rugged GE C2950 Cycoloy plastic
Power Supply Required
Voltage 24 Vac ± 10%, 26 Vdc (25 V min, 30 V max), 50 to 60Hz,
VA 20 VA
Surge Protection
Underwriters Laboratories UL 916(Canadian STD C 22.2 No.205-M1983)
FCC Part 15-Subpart B-Class A
CE Yes
LonMark Certified
No - but LonWorks compatible
Information not provided
BACnet (BTL) Certified
Not submitted for testing
Information not provided