Brand: ERO Electronic (Siebe Group / Eurotherm family).
Model: ISR.025.400.000 industrial solid state relay with factory‑matched aluminium heatsink, panel‑mount bracket, and front status LED.
Condition: New old stock / never used. The relay and heatsink assembly remain in the original ERO Electronic cardboard box with instruction leaflet; terminals and mounting hardware show no signs of installation, while the box has shelf/storage marks from long‑term warehouse keeping.
Technical details (based on ISR/ISL datasheet family – buyers should confirm exact ratings on the product label and included leaflet):
Type: Single‑phase AC solid state relay with SCR output, zero‑cross switching
Nominal load voltage: 400 Vac rms (typical operating range about 24–530 Vac for this family)
Nominal current: 25–52 A AC depending on cooling and duty cycle
Control input: 4.5–35 VDC logic, optically isolated
Assembly: Black relay module clipped to finned aluminium heatsink with panel‑mount lugs and covered terminals, designed for vertical mounting and natural convection cooling
Heavy‑duty SCR design provides reliable switching for resistive and many inductive loads with long electrical life.
Integrated heatsink simplifies thermal design; no need to size and mount a separate heat spreader.
Wide control‑voltage range (4.5–35 VDC) makes it easy to drive directly from PLC outputs, temperature controllers, or other logic devices.
Industrial process heating, ovens, and plastics machinery using 400 Vac heater circuits.
General AC power switching where fast, silent, and maintenance‑free control is required.
Ideal for panel builders, OEMs, and MRO users needing a robust 25–50 A‑class SSR assembly.
