Operating instructions

3.20 Main Menu - Application
Functions - Group 22
This group contains parameters used for monitoring VLT
HVAC Drive applications.
22-00 External Interlock Delay
Range: Function:
0 s * [0 - 600
s]
Only relevant if one of the digital inputs in
parameter group 5-1* has been programmed for
External Interlock [7]. The External Interlock Timer
will introduce a delay after the signal has been
removed from the digital input programmed for
External Interlock, before reaction takes place.
22-01 Power Filter Time
Range: Function:
0.50 s * [0.02 - 10.00 s]
3.20.1 22-2* No-Flow Detection
The frequency converter includes functions for detecting if the
load conditions in the system allow the motor to be stopped:
*Low Power Detection
*Low Speed Detection
One of these two signals must be active for a set time
(par. 22-24 No-Flow Delay) before selected action takes place.
Possible actions to select (par. 22-23 No-Flow Function): No
action, Warning, Alarm, Sleep Mode.
No Flow Detection:
This function is used for detecting a no flow situation in pump
systems where all valves can be closed. Can be used both
when controlled by the integrated PI controller in the frequen-
cy converter or an external PI controller. Actual configuration
must be programmed in par. 1-00 Configuration Mode.
Configuration mode for
- Integrated PI Controller: Closed Loop
- External PI Controller: Open Loop
Parameter Description
VLT
®
HVAC Drive Programming Guide
MG.11.CA.02 - VLT
®
is a registered Danfoss trademark 139
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