OE# 303-1AH-C-R1 U05 48V DC Micro ISO 280 4-Pin Relay SPST-NO 20A R1 Suppression, Universal 48V Auxiliary EV HVAC Pump Fan Lighting Control Replacement

48V Micro ISO 280 4-Pin Relay — Compatible with OE# 303-1AH-C-R1 U05Universal 48-volt SPST-NO relay for auxiliary power, EV/industrial control, telecom 48V plants, and 48V golf cart/UTV systems that use Micro ISO 280 sockets.Key SpecsCoil: 48V DC (R1 internal suppression resistor)Contact Form: 1 Form A (SPST-NO), 4-pin Micro ISO 280 footprintRatings: 20A @14VDC resistive; 10A @28VDC; 16A motor/lamp with 80A inrushOperate/Release: 10 ms max / 10 ms maxOperating Temp: −40 to +125 °C; Weight: ~20 gContact Material: AgSnO (silver-tin-oxide)Body Size (approx.): 23.7 × 16 × 15 mm; 2.8 mm terminalsOE Cross-Ref: 303-1AH-C-R1 U05 48VDC (4-pin)Pinout / Wiring30 = Common; 87 = Normally Open (load output)85/86 = Coil (non-polarized for R1 version)What It DoesRestores switching for 48V auxiliaries such as HVAC blowers, condenser fans, coolant/aux pumps, lighting, and general I/O in control panels.Internal resistor helps reduce coil back-EMF and electrical noise.NotesFor 48V DC systems only; not a 12V/24V automotive relay.Match footprint, pin numbers, and current rating to your circuit before installation.Use with proper 48V fusing and, for high-current main power, a dedicated 48V DC contactor.In the Box1 × 48V Micro ISO 280 4-Pin Relay (SPST-NO), compatible with OE# 303-1AH-C-R1 U05

• SPECIFICATIONS & OE CROSS-REF: 48VDC coil, SPST-NO (4-pin), Micro ISO 280 footprint; 20A @14V resistive / 10A @28V; 16A motor/lamps with 80A inrush; −40~+125°C; 10 ms operate/release; R1 suppression. Compatible with OE# 303-1AH-C-R1 U05 48VDC. Verify 23.7×16×15 mm housing, 2.8 mm terminals and pins 30-85-86-87 before purchase.
• INSTALL & LOCATION: Designed for Micro ISO 280 sockets in 48V auxiliary power systems. Typical installation in fuse/relay block, control module, HVAC board, or lighting panel. Pinout: 30 common, 87 output, 85/86 coil (non-polarized R1). Use only with 48V DC circuits.
• COMPATIBILITY SCOPE: Compatible with 48V auxiliary applications including EV mild-hybrid systems, telecom 48V racks, solar battery storage BOS, and golf cart/UTV 48V relay blocks. Not for 12V/24V cars. Cross-check socket type and coil voltage
• COMMON FAILURES SOLVED: Replaces failed 48V relay causing blower, coolant pump, condenser fan, or lighting not operating. Eliminates relay chatter, restores stable switching, reduces EMI. Ensure upstream fuse and load current ≤ rated 20A.
• DURABILITY & PERFORMANCE: AgSnO contacts, mechanical life 10M cycles, electrical life 100K cycles; vibration 5.0G, shock 10G/100G; operating −40~+125°C. Compact Micro ISO design saves space and weight (~20 g).
• COMPLEMENTARY PARTS: Compatible with 280-series relay sockets, 48V inline fuse holders, add-a-relay harnesses, and 48V DC contactors for higher current main power. Combining with proper fusing and contactor helps build reliable 48V auxiliary circuits.