I picked up this (rather unique?) Tektronix spot welder at a sale a couple weeks ago. I haven't figured out whether it needs 120V or 220V service, and it didn't come with a power cord. The power should come through this male socket in the photograph.

enter image description here enter image description here

Let me know if further details are needed. Thanks! Edits: - added front panel image. M

  • \$\begingroup\$ Looks nonstandard. Any other details available? (e.g. model number) \$\endgroup\$ – user28910 Jan 27 at 18:30
  • \$\begingroup\$ I can't find anything that's positively the model number, just serial number 646. Tektronix headquarters is in my area (Portland, OR) and I imagine this was used as a part of their prototyping labs (maybe production?) back in the mid-20th century. I'll try to get measurements of the connector later tonight. \$\endgroup\$ – James Palmer Jan 27 at 18:57

Looks like a variant of NEMA L-series TwistLock. The center hole is obscure. enter image description here

enter image description here

EDIT: closest one so far: 30 A 208Y/120 V L21-30 with two phases omitted. enter image description here

  • \$\begingroup\$ Thanks for the lead! The spot welder only has two pins, but maybe a 4-hole female connect works with it. I'll research these. \$\endgroup\$ – James Palmer Jan 27 at 19:11
  • \$\begingroup\$ @JamesPalmer You’re welcome! Look at NEMA L21-30. One of these three phase variants with only one phase in use by your connector? \$\endgroup\$ – winny Jan 27 at 19:14
  • \$\begingroup\$ Sounds good. I'll measure the spot welder connector tonight and see if it matches the NEMA L21-30 specs. \$\endgroup\$ – James Palmer Jan 27 at 19:31
  • \$\begingroup\$ @JamesPalmer Any success? \$\endgroup\$ – winny Jan 28 at 17:50
  • \$\begingroup\$ Thanks for following up. I measured a (roughly) 0.6" diameter at the pins. That seems to be too small for NEMA L21-30, which from eyeballing the drawing here has ~25mm has close to 1" diameter at the pins. internationalconfig.com/documents/L2130-C.pdf \$\endgroup\$ – James Palmer Jan 28 at 21:33

After following up on winny's direction, it seems that I should be looking for an ML-2R connector.

enter image description here

  • \$\begingroup\$ Correct. Takes me back to the early 70's, building a TV station. Lotsa Tek gear. \$\endgroup\$ – AnalogKid Jan 28 at 21:54

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.