Finder relay with forced pilot contact is a special type of relay, which must meet the requirements of very clear en safety standards.
This finder relay is used in the safety system to ensure the safety and reliability of its operation and help to achieve a safe working environment. The finder relay must itself have at least one normally open and one normally closed forced pilot contact. These contacts must be mechanically connected so that one contact cannot be disconnected and the other cannot be closed (and vice versa).
This requirement is a basic requirement in order to determine the incorrect operation of the circuit. For example, when the normally closed contact cannot be closed, it can be determined that the normally open contact cannot be opened (for example, it is welded to the closed position). In this case, it is necessary to maintain the standard of 0.5 mm contact clearance.
According to en50205, in finder relays with transfer contacts, only single pole normally open contacts and other pole normally closed contacts can be regarded as forced pilot contacts. For the 50 series finder safety relay, this means that the remaining poles cannot be used as forced guidance.
However, the 7S series finder safety relay module only provides normally open and normally closed contacts.