Danfoss VLT Programming Guide

NB!
If Sleep Mode is to be based on No Flow Detection/Minimum Speed, remember to choose Sleep Mode [1] in par. 22-23
No-Flow
Function
.
If par. 25-26 Destage At No-Flow is set for Enabled, activating Sleep Mode will send a command to the cascade controller (if enabled) to start de-staging
of lag pumps (fixed speed) before stopping the lead pump (variable speed).
When entering Sleep Mode, the lower status line in the Local Control Panel shows Sleep Mode.
See also signal flow chart in section 22-2*
No Flow Detection .
There are three different ways of using the Sleep Mode function:
1) Systems where the integrated PI controller is used for controlling pressure or temperature e.g. boost systems with a pressure feed back signal applied
to the frequency converter from a pressure transducer. Par. 1-00
Configuration Mode must be set for Closed Loop and the PI Controller configured for
desired reference and feed back signals.
Example: Boost system.
If no flow is detected, the frequency converter will increase the set point for pressure to ensure a slight over pressure in the system (boost to be set in
par. 22-45
Setpoint Boost ).
VLT
®
HVAC Drive Programming Guide 3 Parameter Description
MG.11.C9.02 - VLT
®
is a registered Danfoss trademark 207
3

Danfoss VLT Specifications

General

Frequency	50/60 Hz
Enclosure	IP20, IP21, IP55, IP66
Series	VLT
Control Technique	Flux Vector Control
Output Voltage	0-Vinput
Control Method	Fieldbus
Communication Interface	PROFIBUS, CANopen
Protection Features	Overload, Overvoltage, Undervoltage, Short Circuit, Ground Fault
Cooling Method	Liquid Cooled
Storage Temperature	-25°C to +70°C
Relative Humidity	5-95% non-condensing
Altitude	Up to 1000m (3280ft) without derating, up to 4000m (13120ft) with derating
Operating Temperature	-10°C to +50°C (14°F to 122°F)