2-13 Brake Power Monitoring
Option:
Function:
parameter 2-11 Brake Resistor (ohm)
), the
DC-link voltage, and the resistor duty time.
[0]
*
Off
No brake power monitoring required.
[1]
Warning 120s
Activates a warning on the display when
the power transmitted during the duty
time exceeds 100% of the monitoring limit
(
parameter 2-12 Brake Power Limit (kW)
The warning disappears when the
transmitted power drops below 80% of the
monitoring limit.
[2]
Trip 120s
Trips the frequency converter and shows
an alarm when the calculated power
exceeds 100% of the monitoring limit.
[3]
Warning & trip
120s
Activates both of the above, including
warning, trip, and alarm.
[4]
Warning 30s
[5]
Trip 30s
[6]
Warning & trip
30s
[7]
Warning 60s
[8]
Trip 60s
[9]
Warning & trip
60s
[10] Warning 300s
[11] Trip 300s
[12] Warning & trip
300s
[13] Warning 600s
[14] Trip 600s
[15] Warning & trip
600s
If power monitoring is set to
[0] Off
or
[1] Warning
, the
brake function remains active, even if the monitoring limit
is exceeded. This may lead to thermal overload of the
resistor. It is also possible to generate a warning via a
relay/digital output. The measuring accuracy of the power
monitoring depends on the accuracy of the resistance of
the resistor (better than
±
20%).
2-15 Brake Check
Option:
Function:
Parameter 2-15 Brake Check
is only active in
frequency converters with an integral dynamic
brake.
Select type of test and monitoring function to
check the connection to the brake resistor, or
whether a brake resistor is present, and then
show a warning or an alarm in the event of a
fault.
2-15 Brake Check
Option:
Function:
NOTICE
The brake resistor disconnection function
is tested during power-up. However, the
brake IGBT test is performed when there is
no braking. A warning or trip disconnects
the brake function.
The testing sequence is as follows:
1.
The DC-link ripple amplitude is
measured for 300 ms without braking.
2.
The DC-link ripple amplitude is
measured for 300 ms with the brake
turned on.
3.
If the DC-link ripple amplitude while
braking is lower than the DC-link ripple
amplitude before b 1%:
Brake
check has failed by returning a warning or
alarm.
4.
If the DC-link ripple amplitude while
braking is higher than the DC-link ripple
amplitude before b 1%:
Brake
check is OK.
[0]
*
Off
Monitors brake resistor and brake IGBT for a short
circuit during operation. If a short circuit occurs,
Warning 25 Brake resistor short-circuited
appears.
[1] Warning
Monitors brake resistor and brake IGBT for a short
circuit and runs a test for brake resistor discon-
nection during power-up.
[2] Trip
Monitors for a short circuit or disconnection of
the brake resistor, or a short circuit of the brake
IGBT. If a fault occurs, the frequency converter
cuts out while showing an alarm (trip lock).
[3] Stop and
trip
Monitors for a short circuit or disconnection of
the brake resistor, or a short circuit of the brake
IGBT. If a fault occurs, the frequency converter
ramps down to coast and then trips. A trip lock
alarm is shown (for example, warnings 25, 27, or
28).
[4] AC brake Monitors for a short circuit or disconnection of
the brake resistor, or a short circuit of the brake
IGBT. If a fault occurs, the frequency converter
performs a controlled ramp-down. This option is
available for FC 302 only.
[5] Trip Lock
NOTICE
Remove a warning arising with
[0] Off
or
[1] Warning
by
cycling the mains supply. The fault must be corrected
first. For
[0] Off
or
[1] Warning
, the frequency converter
keeps running even if a fault is located.
Parameter Descriptions
VLT
®
AutomationDrive FC 301/302
70
Danfoss A/S © 10/2018 All rights reserved.
MG33MP02
3
3
Summary of Contents for VLT AutomationDrive FC 302
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