NTC 8D-20 Power Thermistor 8ohms for Innosilicon Whatsminer PSU

NTC 8D-20 Power Thermistor | 8Ω 6A Inrush Current Limiter for Innosilicon G1286 and Whatsminer P21 PSU

The NTC 8D-20 is a negative-temperature-coefficient power thermistor — 8Ω cold resistance, 6A continuous, 20mm disc package — used as the inrush current limiter on the AC input stage of the Innosilicon G1286 power supply and the Whatsminer P21 PSU. At power-on, the cold 8Ω resistance absorbs the surge into the bulk capacitors; the thermistor then self-heats and drops to near-zero resistance for normal operation.

Operating temperature range -30°C to +150°C. Industry-standard through-hole disc form factor with standard NTC behavior.

When to Replace the NTC 8D-20

• G1286 / P21 PSU won't start — open NTC blocks the inrush path entirely.
• AC fuse blows on power-up — shorted NTC removes inrush limiting; surge fries the fuse and may damage bridge rectifier or bulk caps.
• Visible damage — cracked, burnt, or discolored disc body.
• Resistance check fails — open (OL) or near 0Ω cold = both indicate failure.

NTC 8D-20 Specifications

FAQ — NTC 8D-20 Power Thermistor

Q: How do I test the thermistor?
A: Power off and discharge PSU caps. Measure cold resistance: healthy NTC 8D-20 reads ~8Ω ±20%. OL (open) or near 0Ω = failed; replace. Visible cracks or burns mean replace regardless of resistance.

Q: Different "D" suffix variants — 5D, 8D, 10D, 16D, 20D — what's the difference?
A: The number before "D" indicates cold resistance in ohms. "20" suffix = 20mm disc. Higher resistance = more inrush limiting and more steady-state power dissipation. Match the original part exactly — substituting changes the PSU's inrush profile.

Q: Rework procedure?
A: Through-hole replacement — desolder both leads, install fresh NTC (non-polarized), trim leads flush. The NTC sits in series with the AC input — handle the de-energized board carefully even after discharge.

Q: Bulk pricing?
A: Yes — email contact@lys-sz.com for tray-quantity pricing.

Related products

• NTC 16D-20 16Ω 5A Thermistor
• NTC 20D-20 20Ω Thermistor
• NTC 5D-15 5Ω Thermistor
• MF72-10D15 10Ω NTC Thermistor (APW3+)

Innosilicon G1286 / Whatsminer P21 repair benches stocking NTC 8D-20 thermistors in volume? Email contact@lys-sz.com for bulk pricing. Worldwide shipping from our Shenzhen warehouse.