Danfoss VLT Brake Resistor MCE 101 Design Manual page 25

Programming
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
display a warning or an alarm in the event of a
fault.
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 braking + 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 braking + 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 appears.
[1] Warning Monitors brake resistor and brake IGBT for a
short-circuit, and runs a test for brake resistor
disconnection 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 displaying an alarm (trip locked).
[3] Stop and Monitors for a short-circuit or disconnection of
trip 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 displayed (e.g. warning 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.
MG90O202
Design Guide
2-15 Brake Check
Option:
[5] Trip Lock
NOTICE
Remove a warning arising in connection 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.
2-16 AC brake Max. Current
Range:
100 %
*
NOTICE
Parameter 2-16 AC brake Max. Current has no effect when
1-10 Motor Construction[1] PM, non salient SPM.
2-17 Over-voltage Control
Option:
[0] Disabled
*
[1] Enabled (not
at stop)
[2] Enabled
NOTICE
Do not enable OVC in hoisting applications.
2-18 Brake Check Condition
Range:
[0] At Power Up
*
[1] After Coast Situations Brake check is performed after coast
16-32 Brake Energy /s
Range:
0 kW
*
Danfoss A/S © Rev. 05/2014 All rights reserved.
Function:
Function:
[ 0 - 1000.0 %] Enter the maximum permissible current
when using AC brake to avoid
overheating of motor windings.
Function:
Overvoltage control (OVC) reduces the risk
of the frequency converter tripping due to
an overvoltage on the DC-link caused by
generative power from the load.
No OVC required.
Activates OVC except when using a stop
signal to stop the frequency converter.
Activates OVC.
Function:
Brake check is performed at power
up.
situations.
Function:
[0 - 10000 kW] View the brake power transmitted to an
external brake resistor, stated as an
instantaneous value.
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