The Siemens 3RT2038-1AP04 is a SIRIUS S2-frame power contactor, three main poles, rated for motor switching at 65 A in AC-3 duty at 480 V — that is the rating that governs real induction-motor loads on a 480 V line. At 230 V it carries a 15 hp motor load.
Termination, wiring, and mechanical fit
Main and coil terminals are screw-type, accepting 2x (0.5 to 1.5 mm²) solid or stranded, or 2x (0.75 to 2.5 mm²). That is a standard panel wire range — no need for ferrule adapters on 14 AWG motor leads.
Switching frequency and duty-class limits
This contactor is rate-limited by duty class, not just the headline current. At AC-1 (resistive) it manages 700 operations per hour; at AC-3 (motor start/run) it drops to 500/h; at AC-4 (plugging/inching) it drops further to 150/h. The AC-3e rating mirrors the AC-3 figure at 500/h. If your application cycles faster than these limits — say a rapid-reversing conveyor — you need to step up to a larger frame or accept reduced electrical life.
Environmental and thermal limits
These numbers matter for coordination in a panel where multiple contactors share a bus — the clearing time determines selectivity with upstream breakers.