I Took Apart a Budget Surge Protector!

[@MarkVanderberg]

Last week I was at Siemens North of Atlanta Georgia and needed a power strip for the hotel room. I stopped at a Micro Center and picked up this very same surge protector.

[@MetaphysicalEngineer]

What a coincidence! Was it also on sale for ten bucks in a big clearance bucket? Do you feel more or less confident after seeing what's inside?

[@spacewolfjr]

You seem like a man I could be a best friend with.

[@Raz_Review]

"Hey we won't tell you if things are going wrong... they might be they might not" *insert skeletor laugh*

[@MetaphysicalEngineer]

Seriously! Hence why I now want to see if any consumer grade surge protectors have an accurate indicator!

[@spacewolfjr]

That's an awesome looking table you've got there.

[@MetaphysicalEngineer]

Ah yes, the second (third?) hand workbench so heavy it might as well be bolted to the garage floor. Definitely in need of a paint refresh!

[@spacewolfjr]

@@MetaphysicalEngineer I kinda like it's current look! But I suppose it's wise to protect the wood and ward off Sasquatches

[@MetaphysicalEngineer]

Yeah. Lots of projects were worked on there, long before I was around, so the patina is cool. Painting it a solid color would help the image quality on camera though.

[@marshyspudder]

"Please don't blow up" seconds before disaster

[@MetaphysicalEngineer]

A wise thing to request before turning on a recently repaired gadget! Borrowed that from the HVACR Videos channel!

[@theirisheditor]

I ran into a similar issue with a Kemelo surge protector I recently bought on Amazon. Unlike that APC one, this one not have a separate protection LED and its user guide only mentions about its overload protection breaker and nothing about surge protection, which makes me wonder if it has any MOVs. My previous Belkin surge protector had a separate protection LED that no longer lights up after about 10 years of use, which is the reason I replaced it.

[@MetaphysicalEngineer]

Thanks for the input! Do you remember the full product name of the Kemelo unit you bought or have a link? MOVs are very cheap so it may have surge protection, but I doubt it has thermal fuses or anything else. Belkin seems to have a decent reputation, and I have one of their units with a protection indicator. I'll be taking a closer look at it in the follow up.

[@theirisheditor]

The Kemelo one has the model number FMK235 - It has 8 AC outlets as a tower (2 per side), 4 USB charging ports and a 3M (10ft) lead. My previous Belkin SurgeMaster 8 AC outlet power strip has the model F9M823uk2M. The AC outlets still work, so still useful as a basic power strip.

[@TheAussieRepairGuy]

12 amps at 110v (1320 watts) seems a little under rated to my Australian ear, we have a max power point rating of 2400 watts (10 amps at 240v)

[@MetaphysicalEngineer]

Nominal voltage here is 120 for 1440W. In the states, the NEC lists 80% of branch circuit capacity as max continuous load for durations of more than 3 hours. For durations less than 3 hours loads may equal the branch circuit rated current, so 1800W on a general purpose 15A circuit. This surge protector's overload warning is tuned to alert the user they have reached or exceeded the continuous load rating. Temp rise stabilized around the time I recorded the end of the load test, so I'm confident it will handle indefinite operation at 12A at normal ambient temps. 20A is common for higher power kitchen or utility or workshop branch circuits for 1920W continuous or 2400W short term. Portable devices rated for 20A are not as common and will use a different plug. Some light workshop or refrigeration equipment may have such a plug. Devices such as clothes dryers, air conditioners, etc needing more will use a 208 or 240V dedicated circuit. Three phase service is unheard of in residential applications and only starts to be used in light commercial.

[@TheAussieRepairGuy]

@@MetaphysicalEngineer we commonly have 15a 240v connections for high load. 3 phase is less common but still found in commercial kitchens, workshops, and some residential sheds. Usually 415v. But you can get 240v from a single phase.

[@akiwi2562]

Ditto, for New Zealand, we share the same power standard.

[@TheAussieRepairGuy]

@@akiwi2562 AS/NZS3760 is the test and tag standard I am certified to - NZS - stands for New Zealand.

[@TheGodOfAllThatWas]

My understanding is this is one of the standard Surge Protection circuits. With the other one just moving the location of the thermal fuses so they cut power to the outlets permanently once tripped. That's what they're pointing you to in the manual Not replace the MOV's. Buy a different surge protector. Never noticed the J mismatch before. Kind of upsets me. It's probably banking on the over current to kick in if the MOVs are cooking. In that case I think I actually prefer the design that cuts power to the outlets permanently. At least then a surge has to get past that (blown) fuse.

[@MetaphysicalEngineer]

Yeah the power cut when the L-N MOV cooks and takes out F1 is the final safety measure. But a surge N to G or L to G may well take out MOV 2 or 3 with no outward indication damage has occurred. Hence the confusing instructions to replace a device with compromised protection but the device can't warn the user it is no longer capable of protecting against further hits of that sort. Starting to wonder if the joule ratings on the data sheet is for max single event surge that will degrade the MOV beyond usefulness. While APC has perhaps done testing to find the MOVs can take dozens of much smaller surges spread over time adding up to 800J. MOV failure seems to be thermal in nature, so the smaller the hits and the more spaced out, the longer the MOV will last. Certainly something I'll find out more about in the follow up where I will take apart several more surge protectors.

[@AnnaVannieuwenhuyse]

I'd say skid marks are an unintentional indicator too 😂​@@MetaphysicalEngineer

[@MetaphysicalEngineer]

I'd say one of my power strips suddenly letting the smoke out qualifies for a code brown moment!