GE AF-650 GP Programming Manual page 167

If power monitoring is set to Off [0] or Warning [1], 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 outputs. The measuring accuracy of the power monitoring depends on the accuracy of
the resistance of the resistor (better than ± 20%).
B-15 Brake Check
Option:
3
[0] * Off
[1] Warning
[2] Trip
[3] Stop and trip
[4] AC brake
NB!
Remove a warning arising in connection with Off [0] or Warning [1] by cycling the mains supply. The fault must be corrected first. For Off [0] or Warning [1], the
frequency converter keeps running even if a fault is located.
This parameter is only active in frequency converters with an integral dynamic brake.
B-16 AC brake Max. Current
Range:
100.0 %* [0.0 - 1000.0 %]
B-17 Over-voltage Control
Option:
[0] * Disabled
[1] Enabled (not at stop)
[2] Enabled
166
Function:
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.
NB!
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.
Monitors brake resistor and brake IGBT for a short-circuit during operation. If a short-circuit occurs,
warning 25 appears.
Monitors brake resistor and brake IGBT for a short-circuit, and runs a test for brake resistor disconnection
during power-up.
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).
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 displayed
(e.g. warning 25, 27 or 28).
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.
Function:
Enter the maximum permissible current when using AC brake to avoid overheating of motor windings.
Function:
Over-voltage control (OVC) reduces the risk of the frequency converter tripping due to an over voltage 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.
AF-650 GP Programming Guide