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RJ SERIES INSTALLATION MANUAL
FX10 Control Overview
The FX10 is a microprocessor based control that not only monitors
and controls the heat pump but also can communicate any of this
information back to the building automation system (BAS). This
means that not only does the control monitor the heat pump at the
unit you can also monitor and control many the features over the
BAS. This clearly puts the FX10 in a class of its own.
The control will enumerate all fault conditions (HP, LP, CO, LOC,
and Low Water Coil Temp) over a BAS as well as display them on
a medium user interface (MUI). HP, LP, CO and Low Water Coil
Temp faults can all be reset over a BAS. A Loss Of Charge fault
can not be reset or bypassed until the problem has been corrected.
A MUI is invaluable as a service tool for the building service team.
The unit can be commanded to run by a typical heat pump
thermostat or run based on heating and cooling set points supplied
by a BAS. The control board is wired with quick connect harnesses
for easy field change out of a bad control board. All ECM variable
fan speed settings can be changed over a BAS or with a MUI. The
control has an output programmed to enable emergency heat in
the event that the compressor is locked out. This output can also
be commanded on from a BAS as needed. An alarm history can be
viewed through the MUI and will be held in memory until the unit is
power cycled. Relative humidity can be read by a humidity sensor
and displayed over the network and if you are using an ECM fan
motor the control can enable dehumidification mode based on a
set point in the control. The dehumidification set point itself can
also be changed over a BAS or with a MUI. Dehumidification
mode can also be enabled by the BAS.
The FX10 control has unused analog and digital inputs for field
installed items such as air temperature, water temperature, or
current status switches. The control has unused binary and PWM
outputs that can be commanded over the BAS for field use.
An optional Medium User Interface (MUI) for control setup and
advanced diagnostics is available with some mounting kits, MUIK1
- Panel mount version and the MUIK2-Wall mount version.
Standard Features
Anti Short Cycle
•
High Pressure Protection
•
Low Pressure Protection
•
Low Water Coil Temperature
•
Loss Of Charge Detection
•
Random Start
•
Display for diagnostics
•
Reset Lockout at disconnect or through BAS
•
2 Accessory outputs
•
Optional DDC control add-on
•
DDC Operation and Connection
Other optional network protocol boards that can be added to the
FX10 are:
Johnson Control N2
•
BACnet
•
LonWorks
•
Control and Safety Feature Details
Emergency Shutdown
The emergency shutdown mode can be activated by a command
from a facility management system or a closed contact on BI-2.
The default state for the emergency shutdown data point is off.
When the emergency shutdown mode is activated, all outputs will
be turned off immediately and will remain off until the emergency
shutdown mode is de-activated. The first time the compressor
starts after the emergency shutdown mode has been de-activated,
there will be a random start delay present.
Lockout Mode
Lockout mode can be activated by any of the following fault
signals: refrigerant system high pressure, refrigerant system low
pressure, heating freeze protection, and condensate overflow.
When any valid fault signal remains continuously active for the
length of its recognition delay, the controller will go into fault retry
mode, which will turn off the compressor. After the Compressor
short cycle delay, the compressor will attempt to operate once
again. If three consecutive faults occur in 60 minutes during a
single heating or cooling demand, the unit will go into lockout
mode, turning off the compressor, enabling the alarm output, and
setting the fan back to low speed operation until the controller
is reset. If the control faults due to the low pressure input (BI-3)
being open during the pre-compressor startup check, the control
will go into lockout mode immediately, disabling the compressor
from starting and enabling the alarm output (BO-6). The lockout
condition can be reset by powering down the controller, by a
command from the BAS, or by the holding the ESC and Return
keys on the MUI for 5 seconds.
Water Coil Temperature Limit (AI-5)
The water coil low temperature limit sensor will monitor the liquid
refrigerant temperature entering the water coil in the heating mode.
If the temperature drops below the water coil low temperature
limit trip point for the recognition delay period, the condition will
be recognized as a fault. The water coil low temperature limit
trip point will be factory set for 30°F and will be field selectable
for 15°F by removing a jumper wire on BI-5. The water coil low
temperature limit fault condition will be bypassed 2 minutes at
normal compressor startup, to allow the refrigeration circuit to
stabilize. If the water coil low temperature limit sensor becomes
unreliable at any time compressor operation will immediately
be suspended until the problem is corrected. This should be
displayed as an alarm on the BAS and the MUI. This alarm will be
reported a “Water Low Temp Limit” fault.
Optional Controls - FX10 cont.
