Square D 8501XDO40V53 Nema Control Relay Brand: Square D. Part Number: 8501XDO40V53. Square D NEMA Control Relay, Type X, Series: 8501X, 10 A AC/5 A DC, 24 VDC Coil, 4NO 4 Form A Contact Form, 5/10 A at 600 V AC Contact, 4 Pole, Panel Mounting, Screw Clamp Terminal, -40 to 160 deg F, 2.23 in W x 3.56 in H x 5.17 in D Dimensions. Additional Description: SQD -8501XDO40V53 RELAY 600VAC 10AMP NEMA +OPTIONS. Catalog Description: Relay, Harmony 8501X, machine tool, coil, 10A resistive at 600V AC, 24V DC, 4NO..