Hello groupfellows.
I am looking for a Mechanical Relay that will serve as the
disconnecting element in a "fail safe" interlock system.
1. This mechanical relay has to be a "Positively driven contacts
operation" or "Force guided contacts operation" - this means that if
the main contacts of the Relay are seized or welded together, than
auxiliary contacts of the relay (that are mechanically connected to
the main contacts) will also not open. Therefore, the seize or welded
situation of the main contacts can be detected through the auxiliary
contacts. (Thanks to Chris Dupres for coming up with this
information)
In addition, the relay should also:
2, Have contacts rating of 230 VAC, 6 A minimum
3. Have contacts separation of 3 mm minimum, or
1.5 mm minimum if two main contacts are
provided and can be connected in series.
4. Have coil rating of 24 VDC or less
5. Have the coil separated from the contacts by at least 4 mm
spacing, 6.4 mm creepage distance.
I have looked at a relay type G7D - 412S, by OMRON. It fulfills the
basic (item 1) and other requirements, but fails to fulfill item 3 -
it has contacts separation of less that 1.5 mm.
If you know of Relay manufacturers that manufacture such relays,
please let me know !
Regards, Israel Yeshurun. Scitex Corp.
