Would this work fine on AC?

TLDR is Filament lamps don't care about polarity, so their LED replacements should not either.

I have not done extensive research on this but my understanding of historic origins of 'indicator lamps' was original old telephone exchanges and Western Electric (the manufacturer of telephone equipment) standardized these and since the filament was small and heavy duty they can tolerate AC or DC.
Later control panels, main frame computers, machinery adopted these standard sizes as they were already mass produced at the time for the phone company.. when LED's arrived in order to replace these they have to be non-polarized. My guess is its just inefficient to make every little LED replacement panel indicator lamp compatible with AC as it adds cost and wastes space.
Fun fact some equipment checks for or depends on the resistance of the lamps so a LED replacement can sometimes throw a an error on old equipment. I remember this on old vans with turn signals. So sometimes you have to get a exact match or add a resistor to the circuit.
This shows incandescent filament indicator lamps that are AC or DC various voltages:
1741361735216.png
 
Besoeker3 said:
I have shown the polarity with my own fair hands. Can you not see that?
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Sure you posted a schematic that shows polarity, so what. I could post a picture of a Duracell battery that has polarity markings. The question is about the lamps in the op that say DC but do not have polarity markings, what do you make of that? It seems strange to require DC but have no polarity markings. Can you answer and share your thoughts on that please??
 
electrofelon said:
Sure you posted a schematic that shows polarity, so what. I could post a picture of a Duracell battery that has polarity markings. The question is about the lamps in the op that say DC but do not have polarity markings, what do you make of that? It seems strange to require DC but have no polarity markings. Can you answer and share your thoughts on that please??
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Brace yourself for some nonsense response about how simple something unrelated is.
 
electrofelon said:
Sure you posted a schematic that shows polarity, so what. I could post a picture of a Duracell battery that has polarity markings. The question is about the lamps in the op that say DC but do not have polarity markings, what do you make of that? It seems strange to require DC but have no polarity markings. Can you answer and share your thoughts on that please??
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It's DC according to the original post. At this point we don't know which of the polarities - just that it is DC
 
Have you guys heard of Dubai bulbs? They were built to last longer and perform more efficiently on purpose. The conspiracy about the light bulb cartel is true!
 
winnie said:
Backup, please.

This is not a LED emitter. It is a LED lamp, designed for DC operation.

The original poster has a reason for running this LED lamp on AC power, and was asking for our thoughts on doing so.

The whole point of the current discussion is operating on the LED lamp on AC; it might be simpler to run it on DC, but in that case the discussion vanishes :)
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They might sit behind a bridge simply so it's not sensitive to which way the wedge base is inserted and should operate with flicker at 60 Hz AC, but might not operate at all at 40,000 Hz, such as behind a electronic MR16 transformer. Standard bridge rectifier is not fast enough for this.

Electronic transformers for 12v track lights generally put out HF AC. Conversely, LED MR16s specifically intended for such applications often work with with nominal 12v with fairly wide latitude, with as high as 15v input. I've successfully implemented AC 12v MR16 in automotive applications before.
 
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