Electrical monitoring for blocking functions in e.g. lift operations - having 2 terminal electrical switches operated by movement of each blocking appts.

摘要

The electrical monitoring is for the functioning of movable blocking means housing electrical switches assigned to them. Two terminal switches are operated by the movement of each blocking means. These terminal switches can be monitored by further terminal switches in a fail-safe arrangement. Each circuit has control protection. The monitoring protection for the closing function and the monitoring protection for the opening function of the control protection are assigned to further separate circuits in series with the working or lazy contacts of the three other protection controls. A self-locking contact in the circuit of the monitoring protection for the closing function bridges the working contact of the monitoring protection and the self-locking contact for the lazy contact of the control protection.