1
\$\begingroup\$

Quick Rundown

The original power supply for my heat press machine (for t-shirts, hats, etc) machine went belly up, so I ordered a the only replacement that I could find that resembled the original.

The Problem When I opened the new power supply up, I noticed that the grounding prong on the inside wasn't connected to anything. The original power supply did have a grounding wire that was connected to the chassis by a bolt. To my very-untrained eye, this seems like it would be the same as snipping the grounding prong off a power cable before plugging it in.

So is this thing actually that dangerous? Can I ground it myself?

ground missing

\$\endgroup\$
22
  • \$\begingroup\$ No, it isn’t and that’s illegal in most parts of the world. \$\endgroup\$
    – winny
    Commented Jul 3, 2022 at 19:30
  • \$\begingroup\$ @winny it's not dangerous? Or it's illegal to sell something like that? \$\endgroup\$
    – SuperStew
    Commented Jul 3, 2022 at 19:31
  • \$\begingroup\$ check continuity from the earth pin to the chassis wall \$\endgroup\$
    – tobalt
    Commented Jul 3, 2022 at 19:31
  • \$\begingroup\$ Certainly dangerous. A better than nothing approach if you can’t return it to the seller would be to connect the chassis to the ground pin. Every loose metallic panel needs ground connection too, via cable or sharp lock washers which bite though the paint. \$\endgroup\$
    – winny
    Commented Jul 3, 2022 at 19:32
  • 1
    \$\begingroup\$ If this is the only replacement you can find, I'd look into whether the original can be repaired. But I expect other replacements should be available, they might just not look much like the original (particularly if the machine is old--you might be replacing a bulky, expensive linear supply with a tiny lightweight modern switching supply). \$\endgroup\$
    – Hearth
    Commented Jul 3, 2022 at 19:41

2 Answers 2

0
\$\begingroup\$

Unfortunately some manufacturers, particularly ones in China, seem to treat grounding as an optional extra. If the importer (into your country) isn't going to test the grounding, then they don't bother fitting it.

Unless you are confident that the power supply is double insulated, then it's wrong, and should be fixed. That should not be too hard to do.

\$\endgroup\$
2
  • \$\begingroup\$ How might one fix it? \$\endgroup\$
    – SuperStew
    Commented Jul 3, 2022 at 20:05
  • 2
    \$\begingroup\$ The terminals on the 3-way connector look like they take standard push-on "spade" terminals, probably 1/4" or 6.3mm. Acually, the terminal on the connector is the spade, and you need the part that pushes onto that. Run a suitable ground wire from that terminal to a screw on the case. Ideally, use a ring connector at the screw end. \$\endgroup\$
    – Simon B
    Commented Jul 3, 2022 at 20:53
0
\$\begingroup\$

When a power transformer is used with low voltage high current, a ground wire may not be necessary.

The usual requirement for 2 pronged plugs or without the PE ground connection is "double insulation" for redundancy.

  • otherwise, a link to supplier brand might be useful for further review of safety or more detailed photo's .
  • where did you get this? It likely has no valid certs near the socket.
\$\endgroup\$
3
  • 4
    \$\begingroup\$ You’re not allowed to have a C13 inlet for a double insulated product. C13 + metal chassis = chassis must be grounded. \$\endgroup\$
    – winny
    Commented Jul 3, 2022 at 19:49
  • \$\begingroup\$ I didn't find a website for the manufacturer, but this is their current aliexpress listing. aliexpress.com/item/2251832632599329.html \$\endgroup\$
    – SuperStew
    Commented Jul 3, 2022 at 19:54
  • \$\begingroup\$ Also I got the replacement power supply just a few weeks ago \$\endgroup\$
    – SuperStew
    Commented Jul 3, 2022 at 19:54

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

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