Thursday, September 10, 2015

Review DH Gate 9 Watt Round Dimmable LED Downlight

I act responsibly toward some LED lights advocated to the public in a Pinterest collection:
Residential LED Lighting .

The light is the smallest in this DH Gate offering, ordered at intermediate color temperature "nature white." I expected this would be 3000°K.

$94.60 for ten lights. I find this was an unacceptable risk.

I ordered the ten lights 8/14/2015, coming from China via Hong Kong, carrier DHL. They arrived Oregon, USA, on 9/8/2015.

Here place one at Stage Left in my test stand, to evaluate it by comparison of delivered illumination.

I will have more to say about the dangling converter block hard-wired in close proximity to the luminaire but too large to stuff into any USA lighting junction box.

At Stage Right, the most similar light I have, a Nicor DLS4 , 3000°K, 671 lumens, 100° beam angle.

Here is my delivered-illumination comparison, at full power. The DH Gate light is at least 600 lumens. It is very blue, estimated 4000°K.

Fully dimmed with Cooper DAL 06P dimmer, the Nicor DLS4 achieves lower power.

The converter block seems to have only 8 watts rating. It is huge vs. a RACO 175 junction box.

This is the only DH Gate package labeling.

Since this is a surface-mount light, try it on an ordinary lighting junction box 1 1/2" deep.

The converter block is too tall/ thick, to reside between the luminaire and the box mounting bracket. On short block tethers, this light has no usefulness in USA homes. To use these lights, I must cut off the block, and wire-nut it to extension wires at the junction box. Find then another place, as on an attic wall, to anchor the block. Electricians won't like this.

Think now to disassemble the DH Gate light for study, removing three little screws.

Loose pieces evolve, the aluminum lid, and two paper disks.

Power goes to the periphery of the aluminum housing, not to a disk circuit board. This is edge illumination of the acrylic lens disk.

See the diode array about the lens.

Note poor strain relief where leads are most at-risk.

Back together, and now I am wary of the poor strain relief.

I'm looking for a compact two-pin connector. This is nicely secure, but not compact. This connector is useless where long bell wire leads must remotely place the converter block or some other general DC source.

A second DH Gate light beams up from my test stand, where I prepare to look for backside light leakage.

Take the opportunity to compare color and appearance with Nicor DLS4, 671 lumens, 3000°K. The blue light is directed at the ceiling. More-yellow light is aimed at my test screen. Both beam about 45° away from the camera.

Leakage is very large. Bugs would die here, but they could not crawl in to dirty the lens. The backside leakage corresponds to power inefficiency with edge lighting. Must nearly half of generated light always leak to the backside? If light is directed here, it does not go out the front.

I have printed this report, except additions now, as PDF in English and in Traditional Chinese, where DH Gate invites feedback prior to release of my payment to the seller. I ask to ship all back to the seller, with full refund of my $94.60. I expect the DHL shipping fee will be substantial, and will report it here. I trust the seller will benefit from the feedback I offer.

I engage in this direct commerce with Chinese manufacturers with interest and with reluctance. In effect as a potential buyer for resale, I join others around the world in becoming a LED lighting manufacturer. This is absurd. It will not persist, as the world falls into chaos , driven by the insane "investors" of Wall Street, who in fact live everywhere . The crimes of greed leading to tragedy include trading in derivatives and direct theft through high-speed trading on illegal knowledge. Profiting from arbitrage in wage disparity , that should be illegal anywhere, is the crime I toy with here. Shame on me. I have been a rube here, and must get out of the game.

I wonder how offshore "LED lighting manufacturers" get what they want. One thing they might control through specification is a consistent scale of lighting color temperature .

I have thought there is a three-color scale, 2700°K Warm White, 3000°K Bright White and 4000°K Day Light, Names vary, and I avoid them. I have become rigid, advocating and buying only 3000°K LEDs.

Now with this purchase, I learn that some Chinese manufacturers have another set of scales:
Warm white: 3000-3500°K
Pure white: 4000-4500°K
Cool white: 5000-5700°K

These are in an offering from Spark , Shenzen, China. They may be the same as used by the unknown manufacturers of my DH Gate purchase. Perhaps USA-allowed 2700°K is thought ugly and is not allowed. I reject these ranges, with so many lights that are very blue, perhaps with no applied phosphor or coloring lens.

I have thought it silly that lights are made with matched diodes and coating, of one color temperature. I think this evolves from early adoption of battery-powered LED strips in under-cabinet lighting. Consumers demanded single-color consistency. In my Google + Community, vision of LED Starry Skies , broad-spectrum lights more-naturally illuminate wall colors. Each luminaire has a spectrum of diodes color, or separate stars have variable color, as do stars in our skies. Ideal lighting is from very many small  stars.

How else must an "LED lighting manufacturer" control what he gets? Choices are infinite and are made with chaos. He may ask only for "light bulbs." Dumb. He must do the detailed design for luminaire mounting. He specifies wiring methods that defy consumer choice. Wishes at my Google + Community are:
We progressively surrender most of our point-source bulbs. Those that remain are for decor, not for illumination. Big LED plate lights occupy recessed-light locations. In time lights get smaller, distributed and remote-controlled with DC wiring. Light elements are with standard-everywhere low-voltage connectors like audio jacks. New luminaires are forward-compatible with OLED elements. And - - seeing that PV arrays fail to serve in a disaster if grid-tied, let most lighting and crucial electronics be off-grid. Silly us, to want to generate income with a PV array, in the grid. In this, lights wired as low-voltage DC, auto and marine as the active example, will prevail over now-competitive chip-on-board AC LEDs. Why might we need AC LEDs? Strip boards down to only diodes and wires: that's what lasts forever. All fragile electronics clustered, serviceable, elsewhere.

I think the chances of achieving my vision are better if lights for my market, USA, are made in USA.

At 9/22/2015, I describe the fraudulent offer I might return my lights to DHGate. Sure. Ship them back within seven days. I have learned that the only workable return is by air, and this is least expensive with US Postal Service. The box is 7.5"x10"x14" and weighs 8.4 pounds. 6 to 10 day priority shipment would cost $76.15. 3 to 5 day express costs $102.30. There might be other costs to ensure delivery. NEX , an agent for DHL, has one air shipping option, costing $95. A return is silly, with no net vs. my $94 purchase cost that I now release to the seller. I have nothing to gain by a return, and only might hurt the seller. Silly seller, and every person thinking to take a chance with DHGate or alibaba: Let's stop fooling ourselves about personal e-commerce from China to USA. I hereafter mark all email from DHGate or alibaba, as Spam.

No comments: