Drive Bypass Function; Drive Bypass Delay Time - Danfoss VLT Programming Manual

3 Parameter Description

24-10 Drive Bypass Function

Option:
[0] * Disabled
[1] Enabled
3
[2] Enabled (Fire M Only)
Important! After enabling the Drive Bypass Function, the Safe Stop function (in versions, where included) is not complying with standard
EN 954-1, Cat. 3 installations anymore.

24-11 Drive Bypass Delay Time

Range:
0 s* [0 - 600 s]
238
Function:
This parameter determines, what circumstances will activate the Drive Bypass Function:
If in normal operation the automatic Drive Bypass Function will be activated at following conditions:
At a Trip Lock or a Trip. After the programmed number of reset attempts, programmed in
par. 14-20 Reset Mode or if the Bypass Delay Timer (par. 24-11
before reset attempts have been completed
When in Fire Mode, the Bypass Function will operate under following conditions:
When experiencing a trip at critical alarms, a Coast or if the Bypass Delay Timer expires before reset
attempts have completed when [2] Enabled in Fire Mode. The Bypass Function will operate at trip
at critical alarms, Coast or if the Bypass Delay Timer expires before reset attempts have been com-
pleted.
The Bypass Function will operate at Trip at Critical Alarms, Coast or Bypass Delay Timer if the timer
expires before reset attempts have completed.
Function:
Programmable in 1 s increments. Once the Bypass Function is activated in accordance with the
setting in par. 24-10 Drive Bypass Function
quency converter has been set for a number of restart attempts, the timer will continue to run while
the frequency converter tries to restart. Should the motor have restarted within the time period of
the Bypass Delay Timer, then the timer is reset.
Should the motor fail to restart at the end of the Bypass Delay Time, the Drive Bypass relay will be
activated, which will have been programmed for Bypass in par. 5-40
Delay] has also been programmed in par. 5-41
Relay
, [Relay], then this time must also elapse before the relay action is performed.
Where no restart attempts are programmed, the timer will run for the delay period set in this pa-
rameter and will then activate the Drive Bypass relay, which will have been programmed for Bypass
Function Relay
in par. 5-40 , Function Relay. If a Relay Delay has also been programmed in
On Delay, Relay
par. 5-41 , On Delay, Relay or par. 5-42
must also elapse before the relay action is performed.
MG.11.C9.02 - VLT ® is a registered Danfoss trademark
®
VLT HVAC Drive Programming Guide
Drive Bypass Delay Time
, the Bypass Delay Timer begins to operate. If the fre-
Function Relay
On Delay, Relay
, [Relay] or par. 5-42
Off Delay, Relay
, [Relay], then this time
) expires
. If a [Relay
Off Delay,