SEW-Eurodrive MOVIDRIVE MDA90A-0160-503-X-S00

9
Functional safety
Safety Conditions
Operating Instructions – MOVIDRIVE
®
modular
256
9.3.3 Requirements on the external safety controller
A safety relay can be used as an alternative to a safety controller. The following re-
quirements apply analogously.
• The safety controller and all other safety-related subsystems must be approved for
at least that safety class which is required in the overall system for the respective,
application-related drive safety function.
The following table shows an example of the required safety class of the safety
controller:
Application Safety controller requirements
Performance level d according to
ENISO13849-1, SIL 2 according to
EN62062
Performance Leveld according to
ENISO13849-1, SIL 2 according to
EN61508
Performance level e according to
ENISO13849-1, SIL 3 according to
EN62061
Performance level e according to
ENISO13849-1, SIL 3 according to
EN61508
• The wiring of the safety controller must be suitable for the required safety class,
(see manufacturer documentation). The STO input of the application inverter can
be switched with 2 poles (sourcing output, sourcing/sinking, or serial sourcing) or
with 1 pole (sourcing).
• The values specified for the safety controller must be strictly adhered to when
designing the circuit.
• Electro-sensitive protective equipment (such as light grid or scanner) according to
EN 61496‑1 and emergency stop buttons must not be directly connected to the
STO input. The connection must be realized using safety relays, safety controllers
etc.
• To ensure protection against unintended restart in accordance with EN1037, the
safe control system must be designed and connected in such a way that resetting
the command device alone does not lead to a restart. A restart may only be carried
out after a manual reset of the safety circuit.
• If no fault exclusion is used for the STO wiring according to ENISO13849‑2 or
DINEN61800‑5‑2, the external safety device must detect the following faults in
the STO wiring within 20s depending on the connection type:
– 2-pole sourcing:
Short circuit of 24V at F_STO_P1 or F_STO_P2 (Stuck-at 1)
Crossfault between F_STO_P1 and F_STO_P2
– 2-pole sourcing/sinking:
Short circuit of 24V at F_STO_P1 (Stuck-at 1)
Short circuit of 0V at F_STO_M (Stuck-at 0)
– 2-pole serial sourcing:
Fault exclusion is mandatory
– 1-pole sourcing:
Short circuit of 24V at F_STO_P (Stuck-at 1)
2-pole sourcing:
• In disconnected state, no switch-on test pulses must occur in the sourcing cables.
• In connected state:
24748536/EN – 11/2017