8400 motec | Software Manual
Motor control (MCTRL)
Monitoring
126
L
Firmware
≤
02.00 - DMS 2.1 EN - 03/2011
5.13.4
Brake resistor monitoring (I2xt)
Due to the converted braking power, the brake resistor is thermally stressed and can even
be thermally destroyed by excessive braking power.
The monitoring of the I
2
xt utilisation of the controller serves to protect the brake resistor.
It acts in proportion to the converted braking power.
If the I
2
xt utilisation reaches the switch-off threshold set in
:
will take place.
– The "
OC12: I2xt brake resistor overload
" error message is entered into the logbook.
If the system is dimensioned correctly, the monitoring should not be activated. If
individual pieces of rated data of the actually connected brake resistor are not known,
they have to be identified.
If the DC-bus voltage exceeds the overvoltage threshold due to a braking energy that is
too high, the monitoring for overvoltage in the DC bus is activated ("OU: DC-bus
overvoltage" error message).
Danger!
= "1: Fault"), the response of the monitoring
function stops the braking operation.
In particular for applications such as hoists, check if a stopping of the braking
operation due to the setting of
= "1: Fault" is permissible.
Stop!
Implement appropriate protective measures against thermal overload of the
brake resistor!
Examples:
• Parameterisation of an error response in
and evaluation of the
parameterised error message within the application or the machine control
system.
• Interruption of the mains supply by means of the temperature contact at the
brake resistor and a simultaneous activation of the mechanical brake.
• Evaluating the temperature contact at the brake resistor by the motor PTC
input of the controller.
Summary of Contents for 8400 motec Series
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