Safe stop
Instruction handbook b maXX BM4400, BM4600, BM4700
Document No.: 5.12008.07 Baumüller Nürnberg GmbH
344
of 358
C.3
C.3.4 Application example for machine of category 4
The diagram displays the use and cabling of a Baumüller converter of b maXX 4000 (BM4X3X-
XX2, BM4X4X-XX2, BM4X5X-XX2, BM4X6X-XX2, BM4X7X-XX2) in a machine tool. Complying
with category 4 (EN ISO 13849-1), in this machine tool the safe removal of work pieces at an
open cover, is possible.
Figure 116: Version with two safety relays (BM4XXX-XX2)
The switching-off of the electrical drive motor is executed with three channels.
n S1 (NC contact) has hardware effects on the safety relay of the converter. Only if S1 displays
a closed cover (safe state), voltage is applied at the safety relay input (X102-3). A torque now
can be generated at the motor shaft. The NO contact of S1 is connected with the monitoring
circuit.
n S2 (NC contact) and S3 (NO contact) effect the other safety relay of the converter. Only if S2
and S3 display a closed cover (safe state), voltage is applied to the safety relay input (X103-
3). A torque now can be generated at the motor shaft.
n S3 (NC contact) has hardware effects on the pulse enable input of the converter (X3-5). Only
if S3 displays a closed cover (safe state), voltage is applied to the pulse enable input of the
converter.
n The monitoring circuit is a fail-safe monitoring control of the category 4 (EN ISO 13849-1). It
checks the directly connected switching contacts of the position switch S1 (NO contact), S2
(NO contact) and S3 (NC contact) and the feedback contacts of the safety relay (X102-1/2
NO contact, X103-1/2 NO contact). The control circuit will not receive an enable signal from
the monitoring circuit, if the cover is not completely closed or if a technically impossible state
of the position switch contacts occurs (for example S1 and S2 display different switch states
To Next Page
Loading...
