10.2004
2
Product Description
Siemens AG
6SE7087-6CX87-2DA1
SIMOVERT MASTERDRIVES
When a motor brakes, it feeds electrical energy back to the SIMOVERT
MASTERDRIVES, causing the DC link voltage to rise. The braking unit
is connected in parallel to the DC link and limits the DC link voltage
increase to an acceptable level. The braking unit converts the
generated braking energy to heat in an external braking resistor. The
appropriate resistor must always be connected to the braking unit.
Braking energy cannot be converted without one.
The braking unit is connected to the converter or inverter via the DC
link terminals. When the DC bus voltage reaches a pre-defined limit,
the braking unit automatically turns on and prevents the DC bus voltage
from continuing to increase.
The braking unit operates autonomously of the converter or inverter.
The braking unit electronics are supplied from the DC link voltage.
Braking units can be connected in parallel to enhance braking
performance.
Braking Unit
Product Description
2-1