Is there a pin-compatible replacement for 10D220K?

Several parts share the 2-pin radial disk package, making them physically compatible. However, their electrical characteristics, especially clamping voltage, differ significantly and are not functionally equivalent.

What risks should I check before replacing 10D220K?

The main risk is the clamping voltage. A substitute with a higher clamping voltage (e.g., 77V vs. the original's 43V) will not protect the circuit from the same level of overvoltage events, potentially causing damage.

10D220K Alternatives, Datasheet & Cross Reference | RUILON

Finding a substitute for the RUILON 10D220K varistor requires careful matching of its 22V varistor voltage and 43V clamping voltage to ensure adequate circuit protection. No direct replacements have been identified.

AI replacement insight

Electrical riskhigh

Candidate clamping voltages are 75-115% higher than target, offering inadequate protection.

Package risklow

Candidates use compatible radial through-hole packages.

Can it be replaced directly?

No direct replacement for the 10D220K has been identified. All reviewed candidates have significantly different voltage characteristics that pose a risk to the application.

Best replacement path

Search for 10mm disk varistors with a nominal voltage of 22V, clamping voltage near 43V, and surge current of 500A or more.

Main risk

Using a substitute with a higher clamping voltage may lead to damage in the circuit the varistor is intended to protect.

Recommended alternatives

A form-compatible alternative with a significantly higher clamping voltage that requires careful engineering review.

View details

Alternative comparison matrix

Feature / factor	10D220K	FTR10D390K	FTR10D470K	Compatibility / risk
Package	Disk (Radial)	Disk	Disk (Radial Lead)	Disk / Disk (Radial Lead) — Form factor is compatible.; FTR10D470K: Form factor is compatible.
Voltage	43V	77V	93V	77V / 93V — Clamping voltage is significantly higher, increasing circuit risk.; FTR10D470K: Clamping voltage is significantly higher, increasing circuit risk.
Current	500A	500A	500A	500A — Surge current rating matches.; FTR10D470K: Surge current rating matches.
Power	3.5J	4.6J	5.5J	4.6J / 5.5J — Energy rating is higher.; FTR10D470K: Energy rating is higher.

Application & sourcing insights

Questions & answers

No direct drop-in replacement was found. Alternatives like FTR10D470K exist but have much higher clamping voltages, which poses a significant risk to the protected circuit and requires engineering validation.