Danfoss Metasys N2 Operating Instructions

Group Title Function
20** FC Closed Loop Parameters used to configure the closed loop PI(D) controller which controls the speed of the
pump, fan or compressor in closed loop mode including:
•
Defining where each of the 3 possible feedback signals come from (e.g. which analog input
or the BMS HLI)
•
Conversion factor for each of the feedback signals (e.g. where a pressure signal is used for
indication of flow in an AHU or converting from pressure to temperature in a compressor
application)
•
Engineering unit for the reference and feedback (e.g. Pa, kPa, m Wg, in Wg, bar, m3/s, m3/h,
°C, °F etc)
•
The function (e.g. sum, difference, average, minimum or maximum) used to calculate the
resulting feedback for single zone applications or the control philosophy for multi-zone
applications
•
Programming of the setpoint(s)
•
Manual or auto-tuning of the PI(D) loop
21** Extended Closed Loop Parameters used to configure the 3 extended closed loop PI(D) controllers which for example
can be used to control external actuators (e.g. chilled water valve to maintain supply air
temperature in a VAV system) including:
•
Engineering unit for the reference and feedback of each controller (e.g. °C, °F etc)
•
Defining the range of the reference/setpoint for each controller
•
Defining where each of the references/setpoints and feedback signals come from (e.g. which
analog input or the BMS HLI); programming of the setpoint and manual or auto-tuning of
the each of the PI(D) controllers
22** Application Functions Parameters used to monitor, protect and control pumps, fans and compressors including:
•
No flow detection and protection of pumps (including auto-setup of this function); dry pump
protection
•
End of curve detection and protection of pumps
•
Sleep mode (especially useful for cooling tower and booster pump sets)
•
Broken belt detection (typically used for fan applications to detect no air flow instead of
using a ∆p switch installed across the fan)
•
Short cycle protection of compressors and pump flow compensation of setpoint (especially
useful for secondary chilled water pump applications where the ∆p sensor has been installed
close to the pump and not across the furthest most significant load(s) in the system. Using
this function can compensate for the sensor installation and help to realise the maximum
energy savings).
23** Time Based Functions Time based parameters including:
•
Parameters used to initiate daily or weekly actions based on the built-in real time clock (e.g.
change of setpoint for night set back mode or start/stop of the pump/fan/compressor start/
stop of a external equipment)
•
Preventive maintenance functions which can be based on running or operating hour time
intervals or on specific dates and times
•
Energy log (especially useful in retrofit applications or where information of the actual
historical load (kW) on the pump/fan/compressor is of interest)
•
Trending (especially useful in retrofit or other applications where there is an interest to log
operating power, current, frequency or speed of the pump/fan/compressor for analysis and a
payback counter
24** Application Functions 2 Parameters used to set-up Fire Mode and/or to control a bypass contactor/starter if designed
into the system.
25** Cascade Controller Parameters used to configure and monitor the built-in pump cascade controller (typically used
for pump booster sets).
How to Programme VLT HVAC Drive FC 102 Operating Instructions
MG11F402 - Rev. 2013-12-16 83
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Danfoss Metasys N2 Specifications

General

Brand	Danfoss
Model	Metasys N2
Category	DC Drives
Language	English