Baumuller BUM 62 T, Руководство пользователя

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Installation
34
Mono Power Unit BUM 62 T
5.99009.03
Baumüller Nürnberg GmbH
The function of the safety relay is limited to the prevention of an unexpected starting. The switching of
the safety relay, while the inductor of the motor is rotating, causes an uncontrolled "coasting" of the ma-
chine, a braking with help of the converter is not possible anymore.
Turning off the safety relay has no isolation from the supply system as a consequence. Therefore, mains
potential can be both at the converter and at the motor. The protection against electric hazards has to
be therefore saved with other means (for example master switches) when maintaining, servicing or re-
pairing electrical components of the drive system.
6.4.2 Safety categories
Dependant of the possible hazards (these are rated due to the consideration of the severity of the inju-
ries, the frequency of the length of stay within the hazard area and possibilities in order to prevent haz-
ards) security relevant components of machines have to meet certain safety criteria. The requirements
to safety-based parts are divided into five categories in the standard EN 954-1.
In category B basic demands, in 1 additionally safety-technical proved components and principles are
claimed. In category 2 an error between inspection intervals can lead to a loss of the safety function.
Category 3 accords to the level “the single-error-certainty to recognize errors partially”. The safety-rele-
vant components must be in such a way, that a single error doesn’t lead to a loss of the safety function,
whereat not the complete possible errors can be self-contained recognized by the system. Therefore an
accumulation of unrecognized errors can lead to a loss of the safety function.
Category 4 accords to the level “Self-monitoring”. This component recognizes self-contained possible
errors and signals these in time of the loss of the safety function. Also if up to three from one another
independent errors arise the safety function is always maintained.
6.4.3 The safety relay
The function of the safety relay is executed in fail-safe-technic, also named closed-circuit principle. The
safety function “safe stop” is active, as long as no voltage is applied to the input terminals (X68: 3,4).
Consequently the functioning of the safety function is guaranteed if power failure takes place. In order
to deactivate “safe stop” a voltage of 24 V has to be applied to the terminals, which are intended for this
use (X68: 3,4).
For the external error monitoring of the safety relay´, the instantaneous control state can be interrogated
at its positively driven status signal contact (X68: 1,2). In case there is no voltage applied to the safety
relay (X68: 3,4), that means during the “safe stop”, then the status signal contact is closed (NC contact).
Also a parting of a cable can thusly be recognized as an error.
If the voltage at the input terminals of the relay (X68: 3,4) is switched off, then the converter generates
one or two error messages (F0204 and/or F0206), which it displays on the V-controller. The drive can
only be taken in operation again, if these messages are deleted after a reset of the safety relay with a
reset signal from the controller (for example by X26, pin programmable or over the interface to a bus
system).
WARNING
Both on the motor and at the unit there can be mains voltage although safety relay is switched off.
If required, switch the appliance off-circuit like an appliance without a safety relay - the safety relay
does not switch the appliance and the motor off- circuit!