: Control circuit voltage limits are now generally capped at 120 Vac or 250 Vdc to harmonize with NFPA 79. Emergency Stops
Scanned PDFs of the 3rd Edition often have unreadable tables (Table SB4.1 for SCCR, for example) or missing wiring diagrams. Compliance requires precise numbers; a blurry scan is useless. Ul 508a 3rd Edition Pdf