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Temperature sensitive outdoor light chain?

Temperature sensitive outdoor light chain?

Temperature sensitive outdoor light chain?

(OP)
Hello,

The company I work for sold a lot of outdoor lightchains to Europe for the Christmas season. We bought them in China and when we tested them they were fine. Now in Europe a lot of them flicker. They tell me it is because of the temperature.
In Southern China (+25 degrees Celsius) it is a lot warmer than in Northern Europe (less than 10 degrees Celsius).
Can this be? Are the lights or the adapter temperature sensitive? If so, we are in deep doo doo...


cheers,

GM

RE: Temperature sensitive outdoor light chain?

Were they of the bimetallic blinker type?

I've noticed that many electrical devices are of much shoddier quality these days.  My paper shredder went fubar the other day and it turned out that a power connection was designed to be less than 0.050" from the metal chassis of the shredder, ugh.

Do you have any left that you can test at low temps?

TTFN

RE: Temperature sensitive outdoor light chain?

Just thinking - could it be due to differences in power frequency, i.e., 50 Hz vs. 60 Hz?

God bless!

RE: Temperature sensitive outdoor light chain?

Hi, I would be suprised if it was temperature, more likely your purchase decision was due to the low low price. Did you test all of them or just a supplied "sample". Maybe some chinees shovels are needed to get you out the doo doo.

RE: Temperature sensitive outdoor light chain?

How did you get the lights from China to Europe?  Did they go on a plane?  If so, were they in the pressurized cabin (with your carry-on) or in the unpressurized cargo area (checked baggage)?

RE: Temperature sensitive outdoor light chain?

No input on the light situation but for IRstuff the spacing you describe is not near enough for a UL listed device (assuming power is 120VAC). If the shredder carries a UL stamp then contact UL with your issue (shredder should not have UL).

RE: Temperature sensitive outdoor light chain?

Hello gmensig;

For me thats have correct sense, the temperature on which are operating the blinking ligths.
As may be you know, those lamp chains are in series connection with a bi-metalic switch that open and close according the temperature self-generated for the current pass in this device.
If this kind of thermostat cools very quickly of course the ligths will appear as blinking too fast.

A possible solution can be locate the switch on the chain , and cover with many turns of isolation tape or masking tape in order to delay the action of the switch.
Good luck.
Jorge

RE: Temperature sensitive outdoor light chain?

(OP)
Hi All,

Thanks for the thoughts...
>> mvcjr - As for the difference in frequency, I dunno, we've never had problems with that before. But I will look into that as well.
>> cbarn24050 - We sample check, but the amount of problems we're facing in Europe is not proportional to the amount we've checked in China. As for letting the Chinese shovel the doo doo, they are getting smarter too and start having labour laws...
>> melone - As for cargo, it was shipped by sea...
>> Jorge - I'll check out the bi-metallic switch.

,

GM

RE: Temperature sensitive outdoor light chain?

If they are bimetal flasher lights then check the mains voltage.  That's most likely to change flasher freq.

RE: Temperature sensitive outdoor light chain?

How fast is the flicker? 50 Hz rate, or a second or two? You mentioned an adapter - is it just a plug adapter, or does it contain a transformer, resistor, PTC resettable fuse etc?

RE: Temperature sensitive outdoor light chain?

My guess is oxidation in all the various connections in the light strings and sockets. During shipment, this oxidation builds up and results in unstable resistances. The non linear power drawn by the lamps as the filiments heat along with these corroded connections results in flickering.

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