SEW-Eurodrive MOVIFIT MC, Руководство пользователя, Страница: 21 / 32

5
Electrical installation
Safety-related disconnection MOVIFIT®
Manual – Functional Safety
21
5.2.2 Group disconnection with MOVIFIT® MC
Requirements
For group drives, the safety-related 24 V voltage supply can be made available for
several MOVIFIT
®
devices by a single safety controller.
The maximally permitted number of MOVIFIT
®
devices results from the maximum per-
mitted contact load of the safety controller and the maximally permitted voltage drop of
the DC 24 V supply voltage for MOVIFIT
®
.
Comply with the requirements and notes of the safety controller manufacturer (e.g.
protecting the output contacts against welding).
Observe the requirements in chapter "Safety-related conditions" when routing the
cables.
The cable length between the X24_P (ABOX, X29 terminal) and the safety controller
must not exceed 100 m for to EMC reasons.
Determining the maximum number of MOVIFIT
®
devices
The following factors limit the number of MOVIFIT
®
devices that can be connected to a
group drive:
• Switching capacity of the safety controller
To prevent welding of the contacts, connect a fuse in front of the safety contacts in
accordance with the specifications of the safety controller manual.
The configuration must guarantee that
– the permitted switching capacity is observed according to EN 60947‑4‑1 and
EN 60947‑5‑1
– and the prescribed fuse is installed as defined in the operating instructions of
the safety controller manufacturer.
• Maximum permitted voltage drop in the 24 V supply cable.
During project planning for group drives, observe the cable lengths, cable cross
sections, and the maximally occurring currents for the safety-related 24 V supply
voltage 24V_P. Determine resulting voltage drops. Compare the voltage drops to
the permitted input voltage range of the MOVIFIT
®
devices.
For MOVIFIT
®
MC, you also have to consider the cable lengths to the connected
MOVIMOT
®
drives and their permitted input voltage range. The cross section of
the 24 V cables in the hybrid cable from SEW‑EURODRIVE (type B) is 0.75 mm
2
.
Perform a calculation based on the technical data of the MOVIFIT
®
for each group
disconnection.
29157056/EN – 09/2019