Optional controls - fx10 cont, Fx10 microprocessor and bas system, Control and safety feature details – WaterFurnace Envision Hydronic (NSW) User Manual

Page 34

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34

NSW INSTALLATION MANUAL

FX10 Microprocessor and BAS System

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 of 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,

LOC, and Freeze Detection) over a BAS as well as display

them on a medium user interface (MUI). HP, LP, and Freeze

Detection 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 applying Y1, Y2, and

O commands to the terminal board or commanded through

a BAS. The control board is wired with quick connect

harnesses for easy field change out of a faulty control

board. An alarm history can be viewed through the MUI and

will be held in memory until the unit is power cycled.

The FX10 control has unused analog and digital inputs for

field installed items such as water temperature or current

status switches. The control has unused binary and PWM

outputs that can be commanded over the BAS for field use.

A Medium User Interface (MUI) for control setup and

advanced diagnostics is standard on all NSW units.

Standard Features

• Anti Short Cycle
• High Pressure Protection
• Low Pressure Protection
• Freeze Detection
• Loss of Charge Detection
• Random Start
• Display for diagnostics
• Reset Lockout at disconnect or through BAS
• 2 Accessory outputs

• Optional BAS add-on controls

DDC Operation and Connection

Other optional network protocol boards that can be added

to the FX10 are:

• Johnson Control N2

• LonWorks

• BACnet

- MS/TP @ 19,200 Baud rate

- Limit devices to 40 on a single trunk line.

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, or freeze detection. 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, the unit will go into lockout mode, turning

off the compressor, enabling the alarm output until the

controller is reset. If the control faults due to the low

pressure input 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. The lockout condition can be

reset by powering down the controller, by a command from

the BAS, or by holding the ESC and Return keys on the user

interface for 5 seconds.

Optional Controls - FX10 cont.

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