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VLCA Controller

Primary Control Unit
Date Last Saved: 9/29/2015 4:10:12 PM

Product Name(s): VLCA Controller
Product Description: The Alerton VLCA is a VACnet advanced application controller (B-AAC) containing 16 universal inputs, eight binary outputs and eight analog outputs. The VLCA is BACnet/IP capable and can be connected directly to an IP network for communication across local or campus networks. The VLCA communicates using BACnet/Ethernet and/or BACnet/IP. The VLCA can also be connected to the secondary MS/TP network if needed.
Product Application(s):
Point Quantity Characteristics
Analog Input (AI):
Digital Input (DI):
Universal Input (AI or DI): 16 Thermistor
1000 Ohm Platinum RTD
Dry contact
0 - 10 VDC
4 - 20 mA
Analog Output (AO): 8 0 - 20 mA
0 - 10 VDC
Digital Output (DO): 8 Triac outputs (24 VAC @ 0.5 A)
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? Information not provided
Integral Damper Actuator? Information not provided
Can controller accept occupant override from thermostat? Information not provided
Can controller accept occupancy sensor input? Information not provided
Expander Boards Information not provided
Expansion Device Model #AIDIUIDOAOUOOther
Network Ports, Protocol(s), and Speed(s) Supported
(Note: See 'Architecture' for network details)
(1) - BACnet/IP or BACnet/Ethernet port to primary network @ 10/100 Mbps
(1) EIA-485 port - BACnet MS/TP port to secondary network @ 9.6 - 115.2 kbps (polling; alternate use)
External Communication Ports, Speeds and Access Devices Information not provided
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 None
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) 32-bit processor
Clock Type
Powered, battery-backed
Battery powered
Powered, no battery backing
Clock Synchronization Synched up via standard BACnet Time_Synchronization message by OWS, or by any device which can transmit standard BACnet Time_Synch.
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? No - Battery maintains internal clock only
Battery Type(s) 3.0 V replaceable lithium coin cell
Battery Life 10 year
Backup Battery Operating Time 1.5 years cumulative real-time clock without AC or battery power
Non-Volatile Memory Capacity (EEPROM/Flash)* 4 MB flash ROM
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? 50 trendlogs @ 60 second intervals
25 alarms
What is the controllers role in trending? Memory allocated to supporting BACnet objects, including a minimum of 3 BACnet schedule objects (Standard, Holiday and Event)
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? Information not provided
Programming Method(s) Alerton Visual Logic graphical programming.
Resident vs Non-Resident Program Execution Local control logic is resident and executed at the control unit.
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.)
Other No information provided
Additional Energy Management functions are resident at SI
Additional Programming Functions
DDC Loops (P, PI, PID) P, PI, 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
Upon restoration of power does the controller:
Auto-reboot without operator intervention? Yes
Automatically reset/synchronize the clock? No
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? Yes
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? Yes
Internal hardware failure? Yes
Open/shortened sensor? Yes
Control Enclosure No
Power Supply Required
Voltage 24 VAC
VA 50 - 60 Hz @ 50 VA
Surge Protection Yes
Underwriters Laboratories UL916
FCC FCC Part 15, Subpart B, Class B
CE European CE Mark
LonMark Certified
No - but LonWorks compatible
Information not provided
BACnet (BTL) Certified
Not submitted for testing
Information not provided