Moog MSD C2, Руководство по эксплуатации

Страница: 40 / 72

40
MSD Single-Axis Servo Drive Compact Operation Manual
ID no.: CA97555-001 Date: 04 /201 8
moog
4.15 Brake chopper connection
In regenerative operation, e.g. when braking the drive, the motor feeds energy back to
the servo drive. This increases the voltage in the DC link. If the voltage exceeds a
threshold value, the internal braking transistor is activated and the regenerated power is
converted into heat by means of a braking resistor.
4.15.1 Protection in case of brake chopper fault
WARNING! Risk of injury due to hot surfaces caused by a faulty brake chopper!
• Carelessness may result in serious burns or damage.
If the brake chopper is overloaded the internal brake chopper transistor may be switched on con-
tinuously, which will result in the overheating of the device and the braking resistor. Temperatures
of up to +250 (+482 °F) may be reached. To prevent more serious damage we recommend the
activation of the following software function:
You can activate this function by assigning BC_FAIL(56) to any digital output
(Moog
D
rive
A
DministrAtor
5
►
Subject area "I/O configuration"
►
Digital outputs
►
OSD00 to
OSD02). In the event of a fault the selected output then switches from 24 V to 0 V .
This signal ensures that the s ervo d rive is safely disconnected from the mains supply.
For detailed information on setting parameters refer to the "MSD Device Help".
4.15.2 Design with integrated braking resistor (C3+4+5)
For Servo Drives with an integrated braking resistor (model G394-xxx-xxx-xx2/xx4)
only the peak braking power is stated in the appendix. The permissible continuous
braking power must be calculated. It depends on the effective utilisation of the servo
drive in the corresponding application.
The servo drive is thermally designed in such a way that no energy input by the internal
braking resistor is permitted during continuous operation at rated current and at
maximum ambient temperature.
Consequently, a servo drive design featuring an integrated braking resistor only makes
sense when the effective servo d
rive utilisation is ≤80 % or the braking resistor is
designed for one-off emergency stop. In the event of an emergency stop, only the
thermal capacity of the braking resistor can be used for a one-off braking action. The
permissible energy W
IBr
can be taken from the following table.
4.14.3 Switching in the motor cable
CAUTION! Damage to the device due to switching in the motor cable!
•
Carelessness can cause damage to the device
Switching in the motor cable must take place with the power cut and the power stage disabled,
as otherwise problems such as burned contactor contacts or power stage damage may occur.
To ensure unpowered switch-on, you must make sure that the contacts of the motor
contactor are closed before the servo drive power stage is enabled. At the moment the
contactor is switched off it is necessary for the contact to remain closed until the servo
drive power stage is shut down and the motor current is 0. This is done by inserting
appropriate safety times for the switching of the motor contactor in the control sequence
of your machine.
NOTE:
Despite these measures, the possibility cannot be ruled out that the servo
drive may malfunction during switching in the motor cable.