Crydom D1225 SPST-NO Relay

The Crydom D1225 is a photo-coupled solid-state relay with SPST-NO contact configuration, engineered for AC load switching across 24 VAC to 140 VAC systems. This Series 1 device delivers 25 A maximum load current with SCR output topology optimized for heavy industrial switching demands. Zero-crossing operation minimizes EMI and extends load life, while the back-to-back SCR architecture handles inrush transients up to 250 A peak at 16.6 ms intervals. ## Technical Specifications • Load Voltage Range: 24 VAC to 140 VAC • Maximum Load Current: 25 A • Control Voltage: 3 VDC to 32 VDC • Input Current: 7 mA to 12 mA • On-State Voltage Drop: 1.15 Vrms (maximum) • Off-State Leakage Current: 8 mA RMS (maximum) • Switching Time: 1/2 cycle (maximum) • Blocking Voltage: 600 V • Surge Current Rating: 250 A peak @ 16.6 ms • Dielectric Strength: 4000 V RMS • Input Impedance: 1500 Ohms nominal • Thermal Resistance (J-to-C): 1.02 °C/W • Capacitance: 8 pF ## Key Features • Zero-voltage crossing for resistive load applications • Direct bond copper substrate for superior thermal management • Internal snubber circuitry • Aluminum base plate with UL94V-0 housing • Screw terminal connections (4-pin) • Optional LED input status indicator (G option) • Optional overvoltage protection module (P option) • Epoxy-free design with anti-rotation barriers ## Typical Applications Heater control, motor soft-starts, lighting systems, industrial process automation, and AC equipment switching in temperature-controlled environments (-40 °C to +80 °C). ## Compatibility & Integration Panel or chassis mount hockey-puck package measuring 57.3 × 44.5 × 22.6 mm. CE, CSA, TUV, and UL approved per EN 60950-1 with Level-3 EMC compliance. RoHS compliant with no SVHC content.