Control Circuits With DC Bus Short Circuit (ZKS)
If you control the mains contactor in the supply unit by an emergency stop re‐
lay and short-circuit the DC bus, you achieve a high degree of safety with lit‐
tle effort. The monitoring functions of the drive system are then used in the
most effective way.
DC bus short circuit at HMV without integrated circuit for DC bus
short circuit
Use HLB01 DC bus resistor units for DC bus short circuit.
It is not recommended to short-circuit the motor connections.
Application
Use this variant, when
●
only motors with permanent magnet excitation are connected
●
motors with permanent magnet excitation and asynchronous motors (in‐
duction machines) are connected
●
the emergency stop switch has to be duplicated or a safety door moni‐
tor, for example, is required
●
your drive system has an extensive emergency stop circuit
Maximum resistance of control circuit
The pickup current of the auxiliary relay for control of the mains
contactor flows via the emergency stop circuit. In order that the
mains contactor picks up reliably, the total resistance of the emer‐
gency stop circuit taking effect between connections X32/1 and
X32/9 has to be less than 45 Ω!
Features
Due to the DC bus short circuit, motors with permanent magnet excitation
can be shutdown with deceleration even if the electronic system of the drive
is disturbed. In order to trigger a DC bus short circuit in such a case, the Bb
contacts of the drive controllers have to be connected in series with the con‐
trol contact and wired in the emergency stop circuit. The DC bus short circuit
only takes effect in the case of drive failure. If emergency stop is actuated,
asynchronous drives therefore are braking, too.
When the Bb contacts of the supply unit are connected in series with the con‐
trol contact in the emergency stop circuit, the DC bus short circuit is only trig‐
gered in the case of a supply unit error.
In the case of emergency stop or when the monitors of the supply unit trigger
(e.g. mains failure), the electronic system of the drives shuts them down ac‐
cording to the error reaction that was set.
Personal injury caused by uncontrolled axis
motion!
WARNING
The circuit for DC bus short circuit protects machines in the case of drive er‐
rors. By itself it cannot assume the function of personal protection. In the
case of errors in the drive and supply unit, uncontrolled drive motion can oc‐
cur even when the DC bus short circuit has been activated.
Asynchronous machines do not brake when the DC bus has been short-
circuited. Personal injury can occur according to the machine design.
Use additional monitors and protective devices on the installation side.
Use the "Integrated Safety Technology" by Rexroth.
DOK-INDRV*-SYSTEM*****-PR06-EN-P
Rexroth IndraDrive Drive Systems with HMV01/02 HMS01/02, HMD01, HCS02/03
Bosch Rexroth AG
157/309
Circuits for the Mains Connection
