What is the W1185LC300? The Westcode W1185LC300 is a high-power press-pack (capsule) rectifier diode designed for demanding industrial rectification. Its capsule construction delivers excellent thermal cycling, low on-state losses, and uniform clamping—ideal for heavy-duty converters, DC drives, traction power, electrolysis, and HV rectifier bridges. Key Advantages at a Glance High current capability for robust line-frequency rectifiers and DC links 3 kV class blocking for medium-to-high voltage stacks Press-pack reliability: no wire bonds, symmetric heat flow, easy series/parallel stacking Low thermal resistance with double-side cooling for simplified heatsink design Proven Westcode lineage used across metals, mining, utilities, and transportation Typical Applications Thyristor/diode bridges for large AC & DC drives Traction substations & trackside power supplies Electrowinning / electrolysis (aluminium, copper, zinc) rectifiers HVDC auxiliaries, soft-start stacks, and bulk power supplies Industrial furnaces and high-current plating rectifiers Why Engineers Choose W1185LC300 Thermal headroom: Low RthJK and press-pack symmetry simplify heatsink sizing and extend life. Mouser Electronics Stack-friendly: Capsule format supports series/parallel builds with uniform clamping force. Serviceability: Press-pack devices are straightforward to replace without re-soldering. Proven curves: Clear surge, Zth, and VF characteristics for confident SOA design. Mouser Electronics Selection & Design Tips (to Protect Lifetime & Efficiency) Cooling method: Prefer double-side cooling to achieve the published IF(AV)M and surge margins. Mouser Electronics Clamp force: Maintain 10–20 kN uniform clamp force (per datasheet) to minimize contact resistance. Mouser Electronics Snubber sizing: Avoid oversized capacitors or undersized resistors to limit snubber discharge current spikes. Mouser Electronics Derating: Apply the 0.13%/°C blocking-voltage derating below 25 °C per the rating report. Mouser Electronics Environment: Consider dust, moisture, and vibration; press-pack capsules excel in harsh duty cycles. Cross-Reference & Equivalents Looking for an equivalent 1200 A / 3 kV press-pack rectifier diode from other makes? We provide engineering cross-reference and stack matching (mechanical & electrical) on request to ensure fit, clamp height, and thermal performance align with your design. (Send your current part no., stack drawing, duty cycle, and cooling method for a fast match.) Ordering & Logistics Condition: New, factory-tested Global supply: Priority shipping to India, East Africa, Middle East & EU QC: Each unit inspected for outline, clamp faces, and encapsulation integrity Support: Thermal calculations, snubber guidance, and stack configuration assistance Get a fast quote: Send RFQ with quantity, target lead time, and application notes. Frequently Asked Questions (FAQ) Q1. Can I run the W1185LC300 with single-side cooling? Yes, but expect higher thermal resistance (~0.065 K/W) and lower allowable average current versus double-side. Design conservatively and validate on your heatsink. Q2. What clamp force do I need? Target 10–20 kN uniform force across the capsule during assembly. Verify tool calibration and flatness of clamp plates. Q3. What’s the surge capability? A single 10 ms half-sine at ~9.2 kA (60% VRRM initial) is indicated. Always assess repetitive surges and thermal recovery per your duty cycle. Q4. Is there a higher-voltage drop-in? The same family includes higher voltage grades (e.g., W1185LC380/450) with similar mechanics but different VRRM. Confirm clamp height and stack insulation before substitution.