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Johnson Controls - Metasys Extended Architecture  

Network Control Engine (NCE) - MS-NCE251x (N2 version); MS-NCE252x (Lonworks version); MS-NCE256x (BACnet version)

Primary Control Unit
Date Last Saved: 7/26/2011 3:11:46 PM

Product Name(s): Network Control Engine (NCE) - MS-NCE251x (N2 version); MS-NCE252x (Lonworks version); MS-NCE256x (BACnet version)
Product Description: The NCE25 combines network supervisor capabilities with Input/Output (I/O) point connnectivity and DDC control capabilities. There are versions controlling a trunk communicating via N2, Lonworks or BACnet protocol. Each version can come with an integral display and/or internal modem.
Product Application(s): The NCE controller can be used for general purpose controls including large AHUs, and central plant control. THe unit has 33 I/O points and an SA bus that allows up to 10 wired devices or a wireless conection to sensors.
Point Quantity Characteristics
Analog Input (AI): NA
Digital Input (DI): See Below contact, 50 Hz pulse
Universal Input (AI or DI): See Below 0-10 Vdc, 4-20 mA, 0-600k ohm, contact, 1 Hz pulse
Analog Output (AO): See Below 0-10 Vdc, 4-20 mA
Digital Output (DO): See Below relay, 24 VAC triac, (external or internal power)
Universal Output (UO): See Below 0-10 Vdc, 24 VAC triac
Control Unit Model #:AIDIUIDOAOUOOther
MS-NCE251x - N2 version 8 10 7 4 4
MS-NCE 252x - Lonworks version 8 10 7 4 4
MS-NCE 256x - BACnet version 8 10 7 4 4
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 16 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? NA
Integral Damper Actuator? NA
Can controller accept occupant override from thermostat? NA
Can controller accept occupancy sensor input? NA
Expander Boards
Network Ports, Protocol(s), and Speed(s) Supported
(Note: See 'Architecture' for network details)
MS-NCE251x Optomux (1) N2 bus @ 9600 Kb ps
MS-NCE252x (1) Lonworks trunk at 78 Kbps
MS-NCE256x (1) 10/100 Mbps Ethernet IP and(1) EIA 485 FC Bus port (MS/TP)
All (1) EIA 485 SA bus terminal connection

External Communication Ports, Speeds and Access Devices (1) EIA 232 serial port for connection to operator workstation
(1) RJ-6 jack with optional internal modem
(1) RJ-6 jack connection to SA bus
(1) USB port for external modem
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) optional
Local Display Panel (zone-mounted)
Handheld Interface Device (proprietary device)
PDA (3rd-Party HID)
Zone-Based port (details below)
Other Wireless commissioning converter
Zone-Based Interface Access NA
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) optional
Local Display Panel (zone-mounted)
Handheld Interface Device (proprietary device)
PDA (3rd-Party HID)
Zone-Based port (details below)
Other Wireless commissioning converter
Microprocessor(s) Supervisory Controller 192 MHz Renesas (tm) SH4 7760 RISC processor
Field Controller 20 MHz Renesas (tm) H8S2398 processor
Clock Type
Powered, battery-backed
Battery powered
Powered, no battery backing
Clock Synchronization Information not provided.
Volatile Memory (RAM) Capacity Supervisory controller - 128 MB,
Field controller 1 MB
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) Rechargeable NiMH 3.6Vdc, 500mAh
Battery Life 5-7 years
Backup Battery Operating Time 30 Days
Non-Volatile Memory Capacity (EEPROM/Flash)* Supervisory controller 128 MB Flash,
Field controller 1 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? Information not provided.
What is the controllers role in trending? Stores trend values locally and can upload them to ADS/ADX
Can controller be programmed to 'push' data to archive or are trends 'pulled' from controller? Yes. Data is transferred at defined intervals or when NCE logs are full.
When full, does controller automatically send up trend data, overwrite data, or stop logging data? Automatically sends trend data to ADS historical database. If no ADS is present in the system, NCE will overwrite the data.
Programming Method(s) Metasys software is used to program the controller.
Resident vs Non-Resident Program Execution All program execution is resident. Programming is retained in non-volatile (Flash) memory. Any calculations temporarily stored in RAM are lost.
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) Information not provided.
Automatic PID Tuning Feature
Automatical-Dial Alarm Support Yes, if optional modem is present.
Does controller perform multiple retries and buffer/store alarm until connection is made? Information not provided.
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? Information not provided.
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? Information not provided.
Update all monitored functions? Yes
Generate an alarm if backup battery is dead? Information not provided.
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? Information not provided.
Additional Information (optional)
Self Test Diagnostics
Does controller have internal self-test diagnostics to check:
Processor failure? Information not provided.
Internal hardware failure? Information not provided.
Open/shortened sensor? Information not provided.
Control Enclosure Plastic (ABS+ Polycarbonate UL 94 5VB) housing
Power Supply Required Yes
Voltage Dedicated nominal 24VAC, Class 2 at 50/60 Hz
VA 30 VA maximum
Surge Protection Information not provided.
Underwriters Laboratories UL 916 Energy listing, CSA C22.2, No. 205 CFR47
FCC FCC Class B, Part 15, Subpart B Class A
CE Yes
LonMark Certified
No - but LonWorks compatible
Information not provided
BACnet (BTL) Certified
Yes (B-BC)
Not submitted for testing
Information not provided