FOR the effective protection of man and machine the emergency stop station is the most critical component in a control system and one in which absolute reliability is expected.
In a typical emergency shut down situation, once the mushroom head is actuated a set of contacts are opened and the electrical supply to the system is disconnected, immediately shutting down controlled machinery.
This typical emergency situation is totally reliant on the correct mechanical connection between the operator and the contact block, however if this connection is somehow inadvertently severed, this can lead to catastrophic outcomes.
In developing a means of ensuring and maintaining the correct mechanical connection between contacts and operators, Siemens has developed the new 3SB3 series which, combined with an emergency stop operator, ensures the ultimate safety device for users, from a unique monitored contact block system.
Catalogued 3SB3400-0M this specially designed monitored contact block includes a normally open contact which is internally wired in series with a normally closed contact.
If for any reason the contact block becomes separated from the emergency stop operator, the normally open contact is tripped and automatically opens the control circuit, shutting down the system being controlled.
The 3SB3400-0M is designed to complement the emergency stop operators and with an industry standard low mounting depth is compatible with standard 3SB38 pushbutton enclosures.
By specifying 3SB3400-0M contact blocks with a 3SB35 series metal or 3SB30 thermoplastic emergency stop operators, added confidence and peace of mind is added that control systems are being monitored, providing constant and maintained safety with every operation.