Question about MV Base Insulator Colors in the US during different decades « on: August 27, 2020, 01:16:53 PM » Author: HPS_250
I have found that nearly all of the mercury vapor lamps made in the 1970s will have a blue glass insulator, and all of the ones made in the 1980s will have a black glass insulator. I have only seen this on US-made lamps. Also, I have noticed that lamps from the 1960s will sometimes have a black or blue glass insulator. Is there any specific color for the 1960s or 1990s? Does anyone know why the glass colors changed throughout different decades?
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I’ve always been interested in all kinds of lighting, mainly incandescent and HID, and especially all kinds of sodium lamps (HPS/LPS). I’ll tolerate LED but I’m not a fan of it.
I’m not proud to say that my city has Devolved to LED.

	Re: Question about MV Base Insulator Colors in the US during different decades « Reply #2 on: August 27, 2020, 02:23:26 PM » Author: HPS_250
Quote from: fluorescent lover 40 on August 27, 2020, 02:07:55 PM GE used blue glass insulators from the mid to late 70s. Same for Westinghouse. Not sure about Sylvania as the two MV lamps I have with blue glass insulators might have GE bases. Thanks for the info. I don’t have any GE lamps from the 70s, but I know that Westinghouse definitely used blue glass in that decade. I’m not really sure about Sylvania either, except that I know they used black glass in the 80s. I also know that Ken-Rad lamps from the 60s had black glass, which means that Westinghouse used black glass in the 60s.
		Logged

I’ve always been interested in all kinds of lighting, mainly incandescent and HID, and especially all kinds of sodium lamps (HPS/LPS). I’ll tolerate LED but I’m not a fan of it.
I’m not proud to say that my city has Devolved to LED.