Bosch CL300 Manual page 59

Flexible Automation
4.1.2 Operation
Floating Contact
The power supply unit does not supply the 24 V load voltage for transducers and actuators. This will
The power supply unit communicates with the ZE300/301 central proc
essing unit via a part of the system bus.
The central processing unit receives signals, such as:
Preventive battery fault indication
D
Battery fault
D
Power failure
D
The buffer battery integrated in the power supply unit provides a central
supply of the CL300 memories which are to be buffered (retaining of
remanent timers, counters, and markers) in case of a power failure.
The power supply unit is supplied without buffer battery which must be
ordered separately. Buffer battery operation is set using jumper J2 (see
paragraph 4.1.4).
If the temperature exceeds 70 _C, the controller is deactivated.
When the RAM module or the central processing unit is removed when
the system is off, the power supply unit recognizes the missing module
and signals a battery fault. In this case the ZE does not start.
The power supply unit has a floating contact which opens in the case of a
power failure of the 5 V/12 V voltages or of a central processing unit mes
sage ZE in STOP". The floating contact can be used according to the
requirements of the specific installation.
The signal ZE in STOP" can be interrupted on the NT by Jumper J1 (see
4.1.4 Settings"), causing the floating contact to open only in case of
power failure.
After switching on the power supply unit, the contact remains open until
the power supply is stable. This prevents the contact from switching be
fore the signal ZE in STOP" has reached a defined state.
. Note ,
require an additional external power supply.
System Modules
4−7