LEDs Etc

LEDs and RF Interference

I notice there has been a lot of traffic on this blog about the RF problem with some LED products, where a hearing-aide or a TV or a radio has problems when the LEDs are turned on.

First, LEDs do not produce the radio frequency interference. An LED is simply a diode that emits light when a DC current is run through it. There is no complex circuitry within an LED to create the radio waves.

Second, the power source generating the voltage to run into the diode is what can produce the radio frequency interference. It all depends upon the design of the circuit around the LED chip. Some inexperienced design engineers are taking a simple, cheap approach to providing power to the LED, and their products create the RF interference.

So if someone says to you, "All LEDs generate RF, tell that person he/she does not know what they are talking about. Only LED devices with poorly designed power circuitry have that problem."

Sam Penny, the Prudent RVer at www.prudentrver.com
and the author at www.WasATimeWhen.com

Prudent RVer in Yuma

I wish everyone a great holiday season, and if you are looking for a unique present, LEDs make a lot of sense. We are operating our booth at the Arizona Market Place at 4th and 32nd in Yuma again this year. Come by and see us.

Sam Penny

the Prudent RVer

Combos, the Latest in Configurable LED Lights for RVs

PrudentRVer.com has combined the flexibility of the zipLED with the ZDisk of the W9.RV3N products into an even newer more flexible product. We call them "Combos."

PrudentRVer.com began selling zipLED products three years ago. These allow the customer to use different light bases to fit the variety of lightbulb sockets in an RV and connect various lightsticks to those bases to solve lighting problems.

Last year we introduced the least expensive solution on the Internet for replacement of the 921 bulb in RVs. This product incorporated the 6 and 10 LED chip designs of the RV2N and RV3N ZDisks.

This summer, at the Escapade in Gillette, WY, Nancy Lessor-Adamo, the LED Lady, began to experiement with how to attach the ZDisk to a zipLED base and created two new products, the B15.ZD6 and the B15.ZD10. She called these products the "Combos." You can see them at www.PrudentRVer.com.

This combination of technologies allows us to provide 200 lumens of light in a flexible solution to fill B15s and B15d sockets in 12volt systems. The voltage regulation features of the ZDisks provide an even better LED product for your RV or boat. Give it a try.

sam

Whither RV LEDs

LED lighting for RVs is a very small niche market. There are not many RVs (compared to homes and businesses) and the primary selling point is to replace existing light bulbs with something better.

The prudentrver.com has worked with Neutek over the past five years to find the best implementation for RV bulb replacements and to find the best kind of light for RVers. We believe we have done a very credible job and have a product line that many are happy with.

Unfortunately, we are a flea on the end of a dog's tail and are being tossed around like a piece of flotsam in the ocean. There are many who have looked at our product and "knocked" it off, making replications at a cheaper price. Unfortunately, they most often did not understand the fine points of the technology and so miss the mark on product quality, and they do not understand the fine points of the kind of light people in RVs want and need. It is not the blue-white lite that is so easy to make with LEDs, it is a high-CR natural warm white that works in that environment.

At this time we are making re-orders for product we have qualified and purchased in the past, but our suppliers in China (the only source) have upped the minimum order quantity by a factor of 10. Our business is growing, but not that fast. So we are stuck between a rock and a hard place.

I am not sure how it will all work out. We are in negotiations and hope to find some way of surviving and still providing what we believe is the best LED lighting out there, but there is the danger that we may not survive. For those who care, just wanted to let you know we are doing our best.

sam, the Prudent RVer

Powering LEDs With AC

I am working on a couple of articles on installing LEDs in an AC (Alternating Current) environment, you know, the 120VAC we find in most domestic homes. The biggest push in the industry is to design LED lamps that work well in that market. The 12VDC market of the RVs is really small potatoes.

LEDs are intrinsically DC devices. They are diodes that want the current to flow in only one direction. To use them efficiently in an AC environment requires specialized circuits.

The problem all started with Thomas Edison. He wanted the electrical grid of the USA to be an AC grid and make use of the generators and such he had invented. Tesla wanted a DC grid, but he lost out. Now we have all our home filled with AC power, and the fixtures are designed to work in that environment.

The simple incandescent light bulb (a 60W for example) has an "Edison" base. This is a screw-in and the usual size is 27mm in diameter. The ground line is connected to the socket surrounding the base, and the power is applied to the contact at the bottom of the base. That electrical power supplies the full 120VAC current to the filament inside the bulb. The flow of current causes the filament to heat up to white hot and emit light.

The 60W incandescent bulb emits about 840 lumens of white light. This much light is required because all the light is coming from a single source, and it must be strong enough to fill a large room space.

In an RV the lights run on 12VDC. There are multiple light bulbs, each of which emits in the range of 150 to 250 lumens. Since these are placed throughout the ceiling and walls of the RV, there is no single source of light. Rather, the light is spread out and each source does not have to be so bright as with a 60W bulb.

We have had very good results if we use linear LED lighting in an RV. This spreads the source of the light even more, and makes for good indirect lighting.

So my forthcoming articles will discuss the pros and cons of using AC power for LED lamps. It can be done, but it tends to be more expensive. But it is very hard to convince people to look for a lighting method that does not use the old-style Edison-base bulbs they always have had.

Sam Penny, the Prudent RVer

Advertising on My Website - PrudentRVer.com

I recently began to run a couple of google ads on my website www.prudentrver.com. The purpose is to add some interest to the website, and maybe create some income for our efforts.

What is interesting is that some of the ads that google is selecting to display (I provide the space, they provide the ads) are for LED products. Now some would freak out over this because the competition is moving in on us, but I think it is a great idea. Show people who the competition is, then let them go there, then they will realize how much better our product set is. That is my philosophy.

So, if you visit our website and see an ad for someone else's LED, be our guest and go look. If we are not good enough for you to come back, we don't deserve your business.

Sam Penny, the Prudent RVer

Prudent RVer at Gillette WY for the Escapade

We will have a booth at the Escapade in Gillette SY at the Escapade starting 8/28/2011. Look for us and try out one of our latest LED lights. We still have the best product and price.

I will not be there, but Nancy, the LED Lady, will be minding our store. Come by and say hello.

sam

An LED Solution for Rigs With Too Much Lighting

The fifth-wheel RV that I use at my basecamp has sixteen 12-volt fluorescent fixtures, each containing two F15T8 tubes. Each fixture uses 30 watts (2.2 amps) of 12-volt power to produce an effective 1,100 lumens of white fluorescent light.

If all fixtures are turned ON at the same time, the wattage is 480 watts (40 amps) and produces a rated luminosity of 27,480 lumens. But because of the limited light efficiency of fluorescent fixtures, the fluorescents only provide an effective 17,600 lumens (1,100 lumens each).

Oh yes, since the electrical efficiency of the ballast and lights is only about 50%, they are pumping 240 of those watts into heating the air in my rig.

In my humble opinion, that is just too much lighting (and heating) for an RV, even a large one with 400 sq-ft of space.

My sixteen fluorescent fixtures are grouped into four sets of three each and four singles. By turning OFF two of the three fixtures in each group, we could reduce our consumption to 240 watts (20 amps), and still have an effective luminosity of 8,800 lumens. That helps, but the resultant lighting is lumpy: too bright in some sections and dim in other parts of the rig.

So that is still too much lighting for some of the space we live in, and too little elsewhere. The obvious solution is to switch to LEDs to replace the fluorescent -- and that is what I did.

When I switched to LEDs, I intentionally reduced the amount of light from each fixture by disconnecting the ballasts and installing a single MyT.fLED-12 LightStrip in each fixture. Each fixture now provides an effective 480 lumens of light each, so the total lighting is 7,680, nearly what I could get by turning off eight of the fluorescent fixtures. And the light is constant throughout the rig, just as we want it. At the same time I reduced the electrical load for lighting from 480 to 96 watts, (40 amps to 8 amps).

As an added bonus, on warm summer evenings I no longer have to use nearly 750 watts to power the air conditioner to remove the excess heat produced by the fluorescent fixtures with their inefficiencies. That can easily add up to an additional 3kwhr per evening, so I am saving 4.2kwhr per evening.

At a retail cost of $37.20 each, the cost of converting all sixteen fluorescent fixtures is less than $550 with the 10% quantity discount. I get better light without heat or fluorescent radio interference or having to replace fluorescent tubes. And it takes about 5 minutes to convert a fixture. LEDs are a win-win solution.

Sam Penny, the Prudent RVer

Website Updates

I updated the www.prudentrver.com website today, at least in the catalog pages. I have added a "Find Your Bulb" and "Find Your Fixture" image that link to pages where you can look at all the choices for bulbs and fixtures where LEDs can be used. I will work on the connectivity to provide better information in the future, but for the time being you can see some of the choices and be pointed into the right directions.

I have also added a place for a couple of the Google Ads to be displayed. This is a change in my long standing policy of not having advertising on my website. We will see how it works. The purpose is to provide some new revenue to our business effort, but I do not want to create confusion for those who simply want to find the best in LED lighting. Let me know what you think. Should the ads be there, do they create a distraction, or what?

Sam Penny, the Prudent RVer

MyT.fLEDescents Compared to Stock Fluorescents

We recently moved into a Teton 5th-wheel at our basecamp. We found we had inherited 14 fluorescent fixtures in the ceiling, each containing two F15T8 tubes. Each fixture used 30watts of power to produce an effective output of 1,100 lumens of light.

If we turned on all the lights at the same time, we produced 15,400 lumens of bright white light along with using 4.2Kilowatts per hour. At the current price middle of August of nearly 20cents per kwhr, that came to $0.84 per hour. But at least half of that was wasted in heat, and it took three times as much power to get that extra heat out of the rig ($1.26), so our real cost for all that light was $2.10 per hour!

If this seems to be crazy, it is. First, we would not usually want all that light. So we could turn off some of the light fixtures. That would save some of the power consumption. But when I look around me, I still see 9 of the fixtures turned ON. Then I notice that those fixtures producing the light are all focused on specific areas, and the light is not spread out evenly the way I would want it.

A better solution is to reduce the amount of light coming from each fixture. But with fluorescents, you must power both tubes, and both will be using energy.

I made the remarkable decision that I should replace some of the fluorescent lighting with LED lighting using our MyT.fLEDescent product.

My first attempt was to put a single 12inch strip of MyT.TL2R light strip into a fixture to replace the two F15T8 tubes. The lumen rating of this light strip is 480 lumens, but at least it is all directed downward into the room. I was amazed when I found that the amount of light provided from each fixture was quite sufficient. The rig had been over-lit.

Each of the lightstrips uses 5watts of power (only 17% of the power required by the fluorescents) for the same fixture, and the power used to generate heat is less than 15% of that total. So the heat that must be exhausted by the air conditioning requires less than 3% of the total power usage. Suddenly, our power consumption with all lights ON dropped from $2.10 per hour to $0.15 per hour (for 0.75kilowatts).

The result is that I could be looking at as much as a 93% reduction in the operational cost of my lighting. Now is the time to charge forward and replace all the lights with LEDs.

Sam Penny, the Prudent RVer