Friday, March 17, 2017

Parmida - Another Disappointing LED Disk Light Offered At Amazon

Silly me. I have tried out this light imported from China by Parmida LED Technologies , Downey, CA. Parmida is another pretender of being a manufacturer, enabling unguided Chinese exports to USA. This light is not mentioned at the glossy Parmida web site devoted to can-loading bulbs and LED conversions.

(4-Pack)- 5/6" Dimmable LED Disk Light Flush Mount Ceiling Fixture, 15W (120W Replacement), 3000K (Soft White), ENERGY STAR, Installs into Junction Box Or Recessed Can, 1200Lm, $45.98 . Sale via Amazon and "LED Light Club," an odd holder of inventory, now out of stock but for 5000°K blue-stuff.

I will rely on LED Light Club for refund upon requested return defective.
LED Light Club, Customer Service Phone: 323-593-5205, Amazon Business Seller, Established 2015, Retailer, Top Brands Parmida LED Technologies, LED METRICS.
LED Metrics is an ebay seller of stupid LED A19 bulbs all out-of-stock.
This sounds about as dangerous as making a direct purchase of something cheaper than its cost of USA shipping, from a naive Chinese factory as at DH Gate or Alibaba. 

My first negative impression of these lights was in absolute inability to disengage the lens with the intuitive counter-clockwise force of palm friction, for the first box. The lens came off too easily on the next box, with no detent resistance.

The biggest complaint against this light is the needless concentration of already too-bright diodes, little obscured by the thin lens.

Employ the noted dimensions in the following table of glare comparisons.

There is so much room to disperse the diodes, not used. Where LED lights promise to serve forever, I do not understand this cheapness. $45.98 is a low price for four bright and durable luminaires, but why shouldn't we wish to pay a bit more, for lights less glaring? Here put meaning to the glare numbers diode luminance and array luminance by a few summaries.

We should want diode luminance numbers less than 2, and array luminance less than 1. Where numbers are not offered on packaging and in marketing comparisons, there is chaos in product design or lack thereof, to be seen as inconsiderate cheapness. The Parmida light is not the worst for glare, but light and heat concentration is such that; it will noticeably warm your hand, unlike any other LED luminaire I have tried. The box backside has an overheating caution (see above).

Worst for glare is visibly-cheap TorchStar :

Here are more comparisons.

My Canon Digital Rebel does not fully capture the glare of the Parmida light. Eyes perceive three brightness zones, one perhaps 2" diameter at center, of dancing angry white sparks.

Let's accuse poor guidance from US Department Of Energy, where glare is not reported on packaging, to disadvantage or ban, cheap LED lights that abuse consumer trust. Absent trust, and locked in for many years with poor choices made, we shamefully fail to conserve energy as promised by LED innovation.

Guidance Given By US Department Of Energy:
The only guidance of our government is in the definition of "high efficacy," lamps worthy of promotion. Approved wording for the 2018 International Energy Conservation Code, IECC, states simply:

HIGH-EFFICACY LAMPS.  Lamps with a minimum efficacy of 75 lumens per watt.

Reason: The wide availability and falling prices of LED lamps makes them a cost-effective option for improving residential efficiency. The proposed threshold of 75 lumens/Watt encourages the use of the new technologies while still permitting many better CFL.

This is a deceitful act to continue production of CFL bulbs for another three years, against the public interest. The deceit requires dismissal of known times-two efficiency advantage of directional downlights for practical illumination, vs. antique point-source lighting.

Please see in above tables, that efficacy greater than 75 lumens per watt is a difficult and perhaps expensive or less-durable reach, for LED lights now on offer. All of the LEDs yet are greatly superior to mercury-leaking, delicate, less-efficient CFLs. 

The roughly factor of two disadvantage of a point source in practical (task) illumination demands that lumens count alone must not serve in this standard of the US Department Of Energy: 
The lumens count of a point-source CFL, reduced by half, could never meet a high efficacy standard.

The failure to distinguish between task-useful directional light, and point source light, leads to misinformation in package labeling of "watt equivalents," the wattage of a comparable incandescent not distinguished whether point source or downlight.

The Parmida box claims equivalence to  120 watts of directional lighting. But how could I know the equivalence except by my own side-by-side comparisons?

I believe a standard of the watt equivalence is in a 500 lumens directional LED, compared to a 100 watt point-source incandescent. 1200 directional lumens scaled thus, is 1200/500*100 = 240 watt equivalent point-source. Divide by two for 120 watt equivalent directional incandescent.

At LHS, Parmida. At RHS two 65 watt incandescent floods. The 1200 lumens Parmida should be very similar to 130 watts of incandescent flood, about 1200 lumens.The Parmida is in fact less illuminating.

At LHS, Parmida. At RHS two 72 watt Philips EcoVangage "100 watt" incandescent point-source. The 1200 lumens Parmida is about 60% less illuminating than 200 watts of point source incandescent.

At LHS 900 lumens first-version Sylvania 70732 LED Disk. At RHS two 72 watt Philips EcoVangage "100 watt" incandescent point-source. The 900 lumens, Sylvania is perhaps more illuminating than 200 watts of point source incandescent.

At LHS 900 lumens first-version Sylvania 70732 LED Disk. At RHS, 1200 lumens Parmida. The 1200 Parmida is less illuminating than Sylvania with 900 lumens. I believe this proves less usefulness of LED light highly concentrated at center of a lens. 

Package labeling of equivalent incandescent lighting is consistently of point source. Here is a label of the 2016 version of 6" Glimpse, 850 lumens, 11 watts.

These side by side comparisons, and relating of directional lumens to point source lumens, inform GREAT FOLLY in the quest to get many more lumens from a directional LED than are needed to match the illumination by a point source light of watt equivalence as point source. Why would one construct a directional LED luminaire on a usual eight-foot ceiling to put out 1200 lumens in replacement of a 75, 100 or even a 120 watt point-source incandescent?  Where 1200 directional lumens would match a 240 watt hot-hot-hot point source bulb, is that what was wanted?

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