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PXC Compact Series

Primary Control Unit
PXC Compact Series
Date Last Saved: 12/13/2007 8:59:15 AM

Product Name(s): PXC Compact Series
Product Description: The PXC controller is a programable controller available in 16 or 24 points and capable of standalone operation or communication with other controllers on the primary network.
Product Application(s): General HVAC applications including, Air Handling Units, Chiller/Boiler/Central Plant control and distribution systems, Data Aquisition, etc. The PXC is available with extended temperature range for rooftop control.
Point Quantity Characteristics
Analog Input (AI): N.A.
Digital Input (DI): See Below Dry Contact
Universal Input (AI or DI): See Below Analog Inputs:
0-10 V, 4-20 mA, 10k or 100k Thermistor, 1000 ohm nickel RTD
Digital Inputs:
Dry Contact, Pulse Counter (20hz)
Analog Output (AO): See Below 0-10 V
Digital Output (DO): See Below Class 1 Relay (Form C)
Universal Output (UO):
Control Unit Model #:AIDIUIDOAOUOOther
PXC16 2 3 3 3 5
PXC24 3 5 3 13
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? N.A.
Integral Damper Actuator? N.A.
Can controller accept occupant override from thermostat? N.A.
Can controller accept occupancy sensor input? N.A.
Expander Boards
Network Ports, Protocol(s), and Speed(s) Supported
(Note: See 'Architecture' for network details)
(1) EIA-485 port for proprietary 'P2' network at 1.2 - 115.2 kbps.
(1) 10 Base-T/100 Base-TX for TCP/IP or Ethernet/IP
External Communication Ports, Speeds and Access Devices (1) EIA-232 port with RJ-45 jack @ up to 38.4 kbps
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 No access is available to the PXC from the zone level (connected secondary controllers). The only field interface with the PXC is through its own field interface port.
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 Power PC - MPC852T
Clock Type
Powered, battery-backed
Battery powered
Powered, no battery backing
Clock Synchronization A single workstation is designated as the master time clock. This workstation resets all clocks on the network.
Volatile Memory (RAM) Capacity 16 MB 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? Yes
Battery Type(s) AA Alkaline - (non-rooftop models)
3.6 volt Lithium - (rooftop models)
Battery Life Information not provided.
Backup Battery Operating Time AA Alkaline - 2 months
3.6 volt Lithium - 3 months
Non-Volatile Memory Capacity (EEPROM/Flash)* 8 MB Flash
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? Trend storage is limited to available RAM.
What is the controllers role in trending? Programming resident within SI gathers and stores trend data on-board. At set intervals, data is sent by the SI to workstations or called by the workstation for archival.
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? Old data is overwritten if controller trend data memory fills before being called by archive workstation.
Programming Method(s) Program editing and Modification via Powers Process Control Language (PPCL)
Resident vs Non-Resident Program Execution Resident
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 Adaptive Control auto-adjusting closed loop control algorithm.
Automatical-Dial Alarm Support Information not provided.
Does controller perform multiple retries and buffer/store alarm until connection is made? Information not provided.
Are multiple destinations possible? Information not provided.
Upon controller power loss or hardware failure:
Are network communications affected? Communication on the primary P2 network is uninterupted.
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? Clock function backed by battery. Clock setting is synchronized at regular intervals by workstation.
Update all monitored functions? Yes.
Generate an alarm if backup battery is dead? No, low battery LED will light.
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? Yes
Others? Diagnostics and error codes are provided for various hardware failures, communications failures, and software/programming errors. LEDs are also provided to indicate power faults, processor status and low battery.
Control Enclosure NEMA 1 (3 sizes available)
Power Supply Required 20 - 30 Vac @ 50/60 Hz +/- 5%
Voltage 24 Vac
VA 20 VA
Surge Protection Information not provided.
Underwriters Laboratories UL 865 UUKL (except rooftop)
ULC-C100UUKL7 (except rooftop)
FCC FCC Compliance
CE CISPR 22 Class A
European EMC Directive (CE): Industrial Levels
European Low Voltage Directive (LVD)
Australian EMC Framework
LonMark Certified
No - but LonWorks compatible
Information not provided
BACnet (BTL) Certified
Not submitted for testing
Information not provided