james_mcquade
Senior Member
Hi everyone,
we have contracted out some work at the plant. the envorimnent is rated class 2, div 2.
the contractor chose AB 800r style pushbuttons for the work. looking at the paper work, the contractor chose correctly.
i wanted to look elsewhere in the plant and i see AB 800t series pushbuttons and devices
everywhere. while these devices are rated NEMA 4,12, they do not have the hazardous
rating. their logic behind the choice is that the pushbutton is NEMA 4 and the contacts are inside the enclosure. i am also seeing illuminated lights in that series. While i cannot do anything about what is here, i can look forward and do things correctly and replace the pushbuttons with the class 2 div 2 rated ones on a timetable basis(or replace everything if allowed).
my question is, is their reasoning valid? do the NEMA 4 rated pushbuttons protect the contacts inside the enclosure enough to satisy the safety requirements? Do the illuminated lights also meet the requirements? i am new to the plant and do not want to be known as a trouble maker right off the bat.
thanks in advance,
james
we have contracted out some work at the plant. the envorimnent is rated class 2, div 2.
the contractor chose AB 800r style pushbuttons for the work. looking at the paper work, the contractor chose correctly.
i wanted to look elsewhere in the plant and i see AB 800t series pushbuttons and devices
everywhere. while these devices are rated NEMA 4,12, they do not have the hazardous
rating. their logic behind the choice is that the pushbutton is NEMA 4 and the contacts are inside the enclosure. i am also seeing illuminated lights in that series. While i cannot do anything about what is here, i can look forward and do things correctly and replace the pushbuttons with the class 2 div 2 rated ones on a timetable basis(or replace everything if allowed).
my question is, is their reasoning valid? do the NEMA 4 rated pushbuttons protect the contacts inside the enclosure enough to satisy the safety requirements? Do the illuminated lights also meet the requirements? i am new to the plant and do not want to be known as a trouble maker right off the bat.
thanks in advance,
james
