The RT9 relay is a fairly standard safety relay, and a similar unit should be able to be sourced from Pilz, Rockwell Guardmaster, Banner or other brand. It will all depend on how the relay is connected on your machine. If you do not understand the safety principles used then get help from some one who does.
What is the differance between a safety relay and a standard relay. As long as the coil voltage, contact current and number of poles is the same can't any relay be retrofitted in?
Often, for safety and insurance requirements it is not possible to replace a control relay except with a relay of exactly the same specification.
If a different specification item of equipment is used, and later there is an accident, insurers may decide that "Unapproved parts were used", and decline any payout.
Thus the person/Company who replaced the item with a non-specification part becomes the target for any lawsuit, compensation, etc.
Kind Regards....
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