BBH SMX Series - Page 117

Installation manual
HB-37420-810-01-25F-EN SMX100 Installation manual.docx Page 117 of 260
Version: 25F
4.3.5.2.3 Wiring with safe cut-off circuit
For safety applications from PI c and higher acc. to EN ISO 13849-1. The external circuit is
controlled directly via a two-channel output. The achievable PL acc. to EN ISO 13849-1 depends
on the use of dynamic testing (see 4.3.2.1 DC) and the PL of the downstream device.
STO
Pl e
IQQ03
X21
IQQ04
IQQ05
IQQ06
L +
L -
Fig.: Two-channel output in connection with a device with with examined disconnection
4.3.5.2.4 Wiring with two-channel switching-off circuit
Suitable for PI d and higher acc. to EN ISO 13849-1. Use of a two-channel output IQQx in
conjunction with two-channel external wiring with test. Positively guided auxiliary contacts are
especially needed for electro-mechanical devices and message contacts for the valve position
are required for hydraulic or pneumatic components.
The achievable PI depends on the use of dynamic testing as well as MTTF
D
-value of the external
channel. Pl e acc. to EN ISO 13849-1 can maximally be reached!
X12
I13
I14
T1
T2
L +
L -
IQQ03
X21
IQQ04
IQQ05
IQQ06
Fig.: Two-channel output in connection with two-channel switching-off circuit with testing