{"product_id":"whatsminer-p21-power-supply-psu-transformer","title":"Whatsminer P21 Power Supply Transformer for Maximum Efficiency and Reliability","description":"\u003ch2\u003eWhatsminer P21 Power Supply Transformer | High-Quality OEM Replacement for P21 \/ P21D \/ P21E PSU Repair\u003c\/h2\u003e\n\u003cp\u003eThe \u003cstrong\u003eWhatsminer P21 PSU transformer\u003c\/strong\u003e is the main isolation and energy-transfer component on the \u003cstrong\u003eWhatsminer P21 power supply\u003c\/strong\u003e primary stage. Provides \u003cstrong\u003egalvanic isolation between the AC mains side and the DC output side\u003c\/strong\u003e, plus voltage regulation and power-stage protection against overvoltage, undervoltage, sudden impact, and power-failure events. Direct OEM replacement when the original fails after extended duty or a fault event.\u003c\/p\u003e\n\u003cp\u003eWhen the transformer fails, the P21 PSU typically presents as completely dead with no output even when the primary controller is alive. Visible symptoms include burnt windings, audible buzz at start-up, or shorted primary-to-secondary reading. A fresh transformer restores full power transfer at the spec ratio.\u003c\/p\u003e\n\u003ch3\u003eWhen to Replace the P21 Transformer\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003ePSU no output\u003c\/strong\u003e with primary controller confirmed healthy — transformer failed.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eVisible damage on the transformer body\u003c\/strong\u003e — burnt windings, melted insulation, cracked ferrite core.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAudible buzz at start-up\u003c\/strong\u003e — degraded transformer with mechanical resonance.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eShorted primary-to-secondary reading\u003c\/strong\u003e on insulation-resistance test — galvanic isolation breakdown.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBurning smell from the PSU\u003c\/strong\u003e not present in normal operation — winding insulation failure in progress.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch4\u003eWhatsminer P21 Transformer Specifications\u003c\/h4\u003e\n\u003ctable\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth\u003eFeature\u003c\/th\u003e\n\u003cth\u003eSpecification\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eCompatibility\u003c\/td\u003e\n\u003ctd\u003eWhatsminer P21 \/ P21D \/ P21E Power Supply\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFunction\u003c\/td\u003e\n\u003ctd\u003eMain isolation \u0026amp; energy-transfer transformer\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eProtective Functions\u003c\/td\u003e\n\u003ctd\u003eOvervoltage, undervoltage, sudden impact, power failure protection\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eVoltage Regulation\u003c\/td\u003e\n\u003ctd\u003eYes\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePower Protection\u003c\/td\u003e\n\u003ctd\u003eYes\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eGalvanic Isolation\u003c\/td\u003e\n\u003ctd\u003eYes — primary-to-secondary safety barrier\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOEM Spec\u003c\/td\u003e\n\u003ctd\u003eDirect replacement, same footprint and ratio\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e3g\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCondition\u003c\/td\u003e\n\u003ctd\u003eBrand New\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003ch3\u003e\u003c\/h3\u003e\n\u003ch3\u003eFAQ — Whatsminer P21 PSU Transformer\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003eQ: How do I confirm the transformer is the failed part?\u003c\/strong\u003e\u003cbr\u003eA: Power off, isolated from mains. Measure primary winding continuity — should read a few ohms. Measure secondary winding continuity — same. Then measure insulation between primary and secondary windings — should read megohms (galvanic isolation). Low reading = isolation breakdown, replace.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eQ: P21 vs P21D vs P21E — same transformer?\u003c\/strong\u003e\u003cbr\u003eA: Verify the part number on your original transformer before ordering. The P21 family shares similar designs but production revisions may have different secondary winding configurations. Match silk-screen ID exactly if available.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eQ: Replacement procedure?\u003c\/strong\u003e\u003cbr\u003eA: Through-hole component — desolder the primary and secondary leads, lift the transformer carefully (heavy magnetic core may stress PCB pads), clean the holes, fit the new transformer with same orientation. Test continuity and isolation before powering up.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eQ: Bulk pricing for P21 repair benches?\u003c\/strong\u003e\u003cbr\u003eA: Yes — email contact@lys-sz.com for volume pricing on P21 transformer stock plus matched primary-side semis.\u003c\/p\u003e\n\u003ch3\u003eRelated products\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\u003ca href=\"\/products\/whatsminer-p21-switching-power-supply-psu-3300w-c19-plug-200-277vac-50-60hz-20a-max\"\u003eWhatsminer P21 Switching PSU 3300W (full unit)\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/products\/bcx56-npn-power-transistor-high-current\"\u003eBCX56-16 NPN Transistor (Whatsminer P21 PSU)\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/products\/lm2904dr2g-dual-op-amp-whatsminer-p21-psu\"\u003eLM2904DR2G Dual Op-Amp (Whatsminer P21 PSU)\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/products\/18p-data-cable-whatsminer-m21b-psu-power-supply-connection\"\u003eWhatsminer M21B 18P Data Cable\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eWhatsminer P21 PSU repair benches stocking transformer spares in volume? Email \u003ca href=\"mailto:contact@lys-sz.com\"\u003econtact@lys-sz.com\u003c\/a\u003e for bulk pricing. Worldwide shipping from our Shenzhen warehouse.\u003c\/p\u003e","brand":"LYS Shenzhen","offers":[{"title":"Default Title","offer_id":42504833826995,"sku":null,"price":1.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0627\/6710\/4179\/files\/Whatsminer-P21-Power-Supply-High-Quality-Transformer-Replacement.webp?v=1744417998","url":"https:\/\/lys-sz.com\/products\/whatsminer-p21-power-supply-psu-transformer","provider":"LYS Shenzhen","version":"1.0","type":"link"}