Sir adrien62400 . . . . .
“Reading” off the parts stamped on info:
Initially there is the Matsushita family of products logo
Then the 7 relates to the ~ 7mm “slug” size of the active metal oxide element,
which directly relates to its instant power handling capacity.
Finally the 221 decodes to 22 with a final added ONE “zero” . . . .reading out as 220.
Which is the units “middle of the road” DC voltage spec of its breakdown avalanched voltage condition in which it only conducts 1 ma of current.
Digi Key referencing is used, since they carry the Bourns product which still utilizes that same numbering scheme . . . . other brands go off on a complete different tangent in their specific use of referencing.
Your part is # 15 down on this list:
http://www.bourns.com/docs/Product-Datasheets/MOV07D.pdf
Item one on this stocking list:
https://www.digikey.com/products/en/circuit-protection/tvs-varistors-movs/141?k=varistors&k=&pkeyword=varistors&pv1802=40&pv69=80&FV=fffc0076&mnonly=0&newproducts=0&ColumnSort=0&page=1&quantity=0&ptm=0&fid=0&pageSize=25
Hurrry! as they only have 1999 left . . . limit one per customer . . . . pending restocking.
Frankly I think that you are being a Don Quixote, off on a quest for the mythical hidden windmill, in your considering / suspect of this item.
If you happen to have an old tube type radio or a transformer that has a dual 120-120 VAC primary winding, I can teach you how to "fish" . . . .so that you won't be knowledge starved and will be able to evaluate units by your own testing.
73’s de Edd
