Danfoss VLT HVAC Series, Programming Manual, Page: 253 / 338

*Fire Mode deactivated
All other alarms occurring while fire mode activated will be logged as usual.
NOTE!
During fire mode operation all stop commands to the adjustable frequency drive will be ignored, including Coast/Coast inverse and
External Interlock. However, if your adjustable frequency drive incorporates “Safe-Stop”, this function is still active. See Section “How
to Order / Ordering Form Type Code”
NOTE!
If in fire mode, it is desired to use the live zero function, then it will also be active for analog inputs other than that used for fire mode
setpoint/feedback. Should the feedback to any of those other analog inputs be lost, for example a cable is burned, live zero function
will operate. If this is undesirable, the live zero function must be disabled for those other inputs.
Desired live zero function, if a signal is missing when fire mode is active, must be set in par.6-02
Fire Mode Live Zero Timeout Func-
tion
.
Warning for live zero will have a higher priority than the warning “Fire Mode”.
24-00 Fire Mode Function
Option: Function:
[0] * Disabled Fire Mode Function is not active.
[1] Enabled In this mode, the motor will continue to operate in a clockwise direction. Speed will depend on what
is selected in
par 24-01, Fire Mode Configuration .
[2] Enabled - Reverse In this mode, the motor will continue to operate in a counter-clockwise direction. Works only in
open-loop. See
par 24-01, Fire Mode Configuration
.
[3] Enabled - Coast When this mode is enabled, the output is disabled and the motor is allowed to coast to stop.
NOTE!
In the above, alarms are produced or ignored in accordance with the selection in par.24-09
Fire Mode Alarm Handling
.
24-01 Fire Mode Configuration
Option: Function:
[0] * Open-loop When fire mode is active, the motor will run with a fixed speed based on a reference set. The unit
will be the same as selected in par.0-02
Motor Speed Unit .
[3] Closed-loop When fire mode is active, the built-in PID controller will control the speed based on the setpoint and
a feedback signal, selected in par.24-07
Fire Mode Feedback Source
. The unit to be selected in par.
24-02
Fire Mode Unit
. If the motor is also controlled by the built-in PID controller when in normal
operation, the same transmitter can be used for both cases by selecting the same source.
NOTE!
The PID controller can be adjusted with par.24-09
Fire Mode Alarm Handling
, [2] Trip, All Alarms/Test.
VLT ® HVAC Drive Programming Guide 3 Parameter Description
MG.11.C6.22 - VLT ® is a registered Danfoss trademark
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