Danfoss VLT FC 100 Series Programming Manual page 186

Parameter Description
Figure 3.66
Status can be read in the Extended Status Word 2, bit
number 24.
24-10 Drive Bypass Function
Option: Function:
This parameter determines what circumstances
will activate the Drive Bypass Function:
[0] Disabled
*
[1] Enabled 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
14-20 Reset Mode or if the bypass delay timer
(24-11 Drive Bypass Delay Time) expires 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 completed.
[2] Enabled The bypass function will operate at trip at
(Fire M critical alarms, coast or bypass delay timer if
Only) the timer expires before reset attempts have
completed.
®
VLT HVAC Drive Programming Guide
Important! After enabling the drive bypass function, the
safe stop function (in versions, where included) no longer
complies with standard EN 954-1, Cat. 3 installations.
24-11 Drive Bypass Delay Time
Range:
0 s
24-90 Missing Motor Function
Option:
[0]
[1]
24-91 Missing Motor Coefficient 1
Range:
0.0000
MG11CD22 - VLT ® is a registered Danfoss trademark
CAUTION
Function:
[0 - Programmable in 1 s increments. Once the Bypass
*
600 s] Function is activated in accordance with the setting
in 24-10 Drive Bypass Function, the Bypass Delay
Timer begins to operate. If the Adjustable
frequency drive has been set for a number of
restart attempts, the timer will continue to run
while the Adjustable frequency drive tries to restart.
If the motor restarts 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 5-40 Function Relay. If a [Relay Delay] has
also been programmed in 5-41 On Delay, Relay,
[Relay] or 5-42 Off Delay, 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
parameter and will then activate the Drive Bypass
relay, which will have been programmed for Bypass
in 5-40 Function Relay, Function Relay. If a Relay
Delay has also been programmed in 5-41 On Delay,
Relay, On Delay, Relay or 5-42 Off Delay, Relay,
[Relay], then this time must also elapse before the
relay action is performed.
Function:
Select the action to be taken if the motor current
is below the limit calculated as a function of the
output frequency. The function is used for
detecting, e.g., a missing motor in multi-motor
applications.
Off
*
Warning
Function:
[-10.0000 - Enter the cubic coefficient of the
*
10.0000 ] Missing Motor detection function
multiplied by 1,000.
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