Determining the maximum number of MOVITRAC units for group disconnection

The number (n units) of ^®  devices that can be connected to a group drive is limited by the following factors:

1. Switching capacity of the safety relay.
2. A fuse must be connected in front of the safety contacts according to the specifications of the safety relay manufacturer to prevent contact welding.
3. The project planner is responsible for ensuring that the specifications for the switching capacity according to EN 60947‑4‑1, 02/1 and EN 60947‑5‑1, 11/97 as well as on contact fuse protection given in the operating instructions of the safety relay manufacturer are strictly observed.
4. Maximum permitted voltage drop in the 24 V power supply cable.
5. Values concerning cable lengths and permitted voltage drops must be observed during project planning for axis systems.
6. Maximum cable cross section of 1 × 1.5 mm² or 2 × 0.75 mm².
7. Power consumption of STO input X17: Input voltage, see chapter "Technical data".
8. When using self-testing semiconductor outputs, the increased capacitances of STO input X17 caused by group disconnection (parallel connection) might result in diagnostics errors.