SDC 482O4U Square Push Plate Actuator, SPDT

The SDC 482O4U is a single-pole double-throw (SPDT) push plate actuator built into a 4½" square stainless steel faceplate. It's a momentary-contact switch used to trigger door operators, request-to-exit functions, or auxiliary relay logic from a single button press — the standard interface point where a person initiates an automatic door cycle or releases an electrified lock. The 18-gauge stainless steel faceplate is the visible, touched surface in high-traffic entries, so it needs to hold up to repeat mechanical actuation and cleaning chemicals without pitting or fading.

Compatibility

As an SPDT momentary switch, the 482O4U wires into any door operator or access control input expecting a dry-contact push button — automatic door operators, electric strike relays, and general request-to-exit circuits are the typical pairing. It's one plate size within SDC's 480 Series: the same SPDT switch mechanism is offered in Narrow (4½" x 11½"), Single Gang (4½" x 2¾"), 4½" Round, 6" Square, and 6" Round formats (models 482O1U, 482O2U, 482O4RU, 482O6U, 482O6RU and their A/B faceplate-finish variants) if this opening calls for a different plate footprint or mounting box. It's also offered as wireless-compatible in most sizes, so it can pair into a wireless request-to-exit transmitter setup where running conduit isn't practical — the narrow DPDT variant is the one exception to wireless compatibility.

Installation Notes

Mounts recessed, into a surface box, or onto a bollard — pick the mounting path based on the wall or pedestal condition at the opening. Overall depth behind the faceplate is 7/8", so confirm the back box or wall cavity clears that before rough-in. The SPDT contact is rated 2 Amp @ 48VDC resistive for this 4½" square format, enough headroom for most low-voltage door operator and relay inputs without an interposing relay. Contact type is momentary (MO) — the circuit closes only while the plate is pressed, which matters if your controller logic expects a maintained signal instead.

Pair the 482O4U with a compatible access control door operator or exit device from the SDC catalog to complete the opening, and check SDC's broader push plates and panels line if you need a different faceplate size or finish for the same SPDT mechanism. For planning which actuator fits a given door hardware setup, a door hardware and access control buying guide is worth reviewing before ordering. If the opening also needs power for an electric strike or maglock, check compatible access control power supplies rated for the connected load.