Johnson Controls RC Series Engineering Manual page 12

RC SERIES ENGINEERING GUIDE
Controls - FX10
Optional FX10 Control
Main FX 10 Board
The optional FX10 control provides unparalleled capability
in several areas including performance monitoring, zoning,
humidity, energy management, and service diagnosis, and then
communicates it all thru standard DDC protocols like N2, Lon and
BACnet (MS/TP @ 19,200 Baud rate).
The most unique feature is integrating the FX10 into the unit as
both the heat pump and DDC controller providing both a cost
advantage and providing features not typically found on WLHP
controls. This integration allows heat pump monitoring sensors,
status and service diagnosis faults to be communicated thru the
DDC direct to the building automation system (BAS), giving building
supervisors detailed and accurate information on every piece of
equipment without removing an access panel.
FX10 Advanced Control Overview
The Johnson Controls FX10 board is specifically designed for
commercial heat pumps and provides control of the entire unit
as well as input ports for Open N2, LonTalk, BACnet (MS/TP @
19,200 Baud rate) communication protocols as well as an input
port for a user interface. The user interface is an accessory item
that can be used to aid in diagnostics and unit setup. A 16-pin
low voltage terminal board provides terminals for common field
connections. The FX10 Control provides:
• Operational sequencing
• High and low-pressure switch monitoring
• General lockout
• Freeze detection
• Condensate overflow sensing
• Lockout mode control
• Emergency shutdown mode
• Random start and short cycle protection
Short Cycle Protection
Allows a minimum compressor "off" time of four minutes and a
minimum "on" time of two minutes.
Random Start
A delay of 1 to 120 seconds is generated after each power-up to
prevent simultaneous startup of all units within a building after the
release from an unoccupied cycle or power loss.
Emergency Shutdown
A field-applied dry contact can be used to place the control into
emergency shutdown mode. During this mode, all outputs on the
board are disabled.
Freeze Detection Limit
Field selectable for 15° or 30°F (-9° or -1°C)
Installation Options
• Standalone controlled by standard room thermostat
• Standalone with a Zone Temperature Sensor (must have user
interface to change set points beyond the allowed +/- 5°F)
• Integrated into BAS by adding communication module
Accessory Outputs
Quantity 2. One cycled with blower, other with compressor.
User Interface
4 x 20 backlit LCD.
Optional Plug-in Communication Modules -
(compatible with standard BAS protocols)
• Open N2
• LonTalk
• BACnet (MS/TP @ 19,200 Baud rate)
Display
Requires DLI Card/Kit. Up to 2 displays, either 1 local and 1
remote, or 2 remote. (A 2-display configuration requires identical
displays.) Local display can be up to 3 meters from the controller,
power supply, and data communication. Remote display can be
up to 300 meters from the controller. Remote display must be
independently powered with data communication done via 3 pole
shielded cable.
Control Timing & Fault Recognition Delays
Lead compressor "ON" delay ............................................90 seconds
(not applicable for single compressor models)
Minimum compressor "ON" time ...........................................2 minutes
(except for fault condition)
Short cycle delay ..................................................................5 minutes
Random start delay ......................................................0-120 seconds
High pressure fault ............................................................. <1 second
Low pressure fault .............................................................30 seconds
Freeze detection fault ..........................................................30 seconds
Condensate overflow fault .................................................30 seconds
Low pressure fault bypass ....................................................2 minutes
Freeze detection fault bypass...............................................2 minutes
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