Regavolt Variable Transformer Current

From here in the USA, my searches for anything referenced as exactly LD-173 comes up empty.

Here is a link to a published history of Regavolt Variacs. I don’t see anything there that offers any near matches to that number.

https://www.claudelyons.com/resource-centre/a-time-line-of-the-variable-transformer-1933-present-day/

Can you toss us a meatier bone here? Approx age, weight, dimensions… how about a picture or two, maybe a pic of the nameplate?

Hi,

Sorry, but couldn't upload a picture. It is 32cm in diameter, approximately 10cm high (the winding) and weighs 78 pounds. Not sure of the age.

Assuming 600 volt insulation, that would be about #12 AWG, probably good for 20-25 amperes in open air, as you postulated.

Thanks for the input. I will go with that value.

I found this on a search "The first models were rated at some 500 VA (200 series) , and were followed a year or two later by larger units rated at about 2 kVA (100 series), and subsequently 5 kVA (50 series)."

Maybe your LD-173 puts it in the 100 series and if so it approx 8 amp however 3mm dia puts it at 25 amp. A bit of an anomaly unless the limitation is the brush current carrying capacity.

Treat it as an ~8 A device, not a 25 A one. Your “anomaly” is real—but it’s explained by system-level limitations rather than the wire itself.