HSR-3D404Z Solid State Relay: Complete Technical Guide for Industrial Automation

What this delivery is: Hanyoung NUX HSR-3D404Z three-phase solid state relays — 40 A per phase, 90–480 VAC load side, 4–32 VDC control input — new in the maker's SOLID STATE RELAY boxes, made in Indonesia per both the record and the face label, uploaded 2025-07-07. A count note first: the delivery record books one piece, but the photos show two units (one in hand, one on the bench, two cartons in the box shot); both numbers stand as reported.

Reading the relay

The HSR-3D404Z is a three-phase SSR in the panel-mount body: a grey chassis on a metal thermal base with a DIN-rail clip behind, six power terminals under a clear protective cover — R, S and T on the line side, U, V and W on the load side — and the control input on the right flank marked INPUT + 4-32VDC. Applying 4 to 32 volts DC across those control terminals turns on all three phases at once; the triac stacks switch at the zero crossing, which is why these relays click nothing and last through millions of operations a contactor could not survive. The face label carries the full rating in one block: LOAD 90-480V a.c 40A 50-60Hz, CE, MADE IN INDONESIA, Hanyoung nux — the Korean maker's Indonesian plant, consistent between the record and the label. Two details matter at 40 A: the metal base is the heatsink interface, so it bolts to a real heatsink with thermal paste, not to a bare panel; and the clear cover stays on until the wiring torque is set, because the terminals are live on both sides when running.

Use notes

Size the heatsink for the real load: a 40 A SSR dissipates roughly a hundred watts per phase at full current, so continuous duty wants a generous finned sink and, above about 30 A, airflow. The 4–32 VDC input takes a PLC transistor output directly — wire the PLC output to + and return to −, no interposing relay needed, and the zero-cross switching keeps the conducted EMI down on resistive loads. For heater banks the three-phase symmetry is the point: one control signal, three legs switched together, no phase walking. If the load is inductive, add an RC snubber or MOV set across the output side and check the holding current against the relay's minimum — same rules as any triac stage. Two SSR records from this series make good comparisons: the FOTEK ESR-100DA-H at 100 A and the Crouzet GN84134140 single-phase 100 A unit.

Photos

Inspection video.

Related products on KOEED

Same family on the storefront: the HANYOUNG HSR-3D304Z solid state relay (30 A sibling). Related reads: the FOTEK ESR-100DA-H and Crouzet GN84134140 SSR records.