Pinball lamp measurements v4

I am working on a project, that gives me the chance to document some data regarding different lamps used for pinball machines. The lamps used are incandescent(regular) 44s and Cointaker frosted cool white LEDs. LEDs equivalent to the Cointaker should give similar results. I chose Cointaker since it is what I use myself.

Version 4 final. Updated January the 6th 2015.

1. Power consumption

Standard 555/44 incandescent bulb. Used for inserts and GI:

Running as CPU controlled(+5V) these draw 0.2 A.
The wattage is 5*0.2 = 1W

Running as GI(+6.3V) they draw 0.24 A
The wattage is 6.3*0.24 = 1.5W

Cointaker 555/44 LED cool white. Used for inserts and GI:

Running as CPU controlled(+5V) they draw 0.02 A
The wattage is 5*0.02 = 0.1W

Running as GI(+6.3V) they draw 0.05 A
The wattage is 6.3*0.05 = 0.3W

2. Temperature measurements

Using a standard 44 incandescent bulb and a Cointaker frosted LED 44 for measurements. The thermometer was placed at the very tip of both subjects. I will make measurements regarding the heat build-up and the heat decay when turned off. Possible error sources are the thermometer itself which needs to be heated and cooled. However, this is the same for both subjects. Seen in relation to each other, it should cancel out.

First, here’s a graph with four lines, two tests for the incandescent and two tests for the LED. This is to see how each behave as both GI and feature(6.3V and 5V)

led1
The graph shows a radical difference between the incandescent and the LED. You can see that all protrude from the same point on the Y-axis. This is the room temperature(23.4 C) when measuring on the desk. The feature(5V) LED almost doesn’t deviate from this value. At the other end, the incandescent(6.3V) is almost at 44 C. Looking at the graph one can tell that there is huge difference between the subjects.

Going to the heat decay time graph(below). This is to show how long it takes for the bulb to reach the room temperature again, when turned off. As seen in the graph above, this is 23.4 C.
led2

I have omitted the two LED tests. Their heat build up was too low to include here or even worry about. Looking at the graph you can see that it takes 12 minutes for the incandescent(5V and 6.3V) to return to room temperature. Being a little more fair, it takes about 3-4 minutes for most of the heat to disperse.

3. Light output, relative

Now let us look at the light output differences between the standard 44 incandescent bulb and the cointaker frosted LED. I have measured using the lux from each subject at both voltages(6.3V and 5.0V). Lux is the SI-standard for measuring illuminance. Since these sources(the incandescent and the LED) are at different places in the x, y, z – plane of a pinball machine, with some being hidden, some being under inserts and all of them being at different distances from the player it would be futile trying to measure the real scalar value of one of these. On top of this, pinball machines are being played in rooms that are lit. This means that the light output from the pinball machine would add almost no light to the room. Therefore, I have chosen to do the measurements of each bulb/LED and voltage in a dark room using a luxmeter at a set distance from the bulb/LED mounted in a 44 socket. Doing this gives me values that are unusable except when looked relative to each other. Here is a graph of the measurements:
led3

As can be seen on the left half of the graph, the luxmeter read 250(no units) for the cointaker frosted LED, and 120(no units) for the 44 incandescent. This shows that the LED has double the output of the incandescent. The same go for the right side of the graph. Again, the LED doubles up. This must mean something when LEDs are used as inserts and you play in a well-lit room.
Possible errors/neglects in the above graph and statements can be that LED doesn’t generally spread the light around as well as incandescents. The lux measurements are made from the front, where the LED is stronger than it is from the sides. However, since it has double the output from the front and the LED is frosted, I will make the bet that the LED is better(higher output) from the sides as well. Keep in mind that colored LEDs take a dive in light ouput! (the same goes for incandescents)

4. Light output comparison between different colors, relative

I have measured the standard frosted LED against its colored counterparts. I wanted to see how much light output is lost to get color. The result are in the graph below. I have included an incandescent as well.

led4
As earlier the numbers means nothing. They are just the numbers from the light measurement at a set distance. Only the comparison is valid. If we look at the white frosted compared to the red frosted, the light output is cut 60%. The other colors are in the same league, with orange being cut by 68%. Still, compared to the incandescent, they are still brighter. But this is very uncertain. In this test, the incandescent are 73% dimmer than the white frosted, but in the earlier test the difference was 50%. This is due to incandescent pinball lamps varying a lot in output. So, whether a colored LED is dimmer or brighter than an incandescent is up to chance or testing each for output.


Conclusion:

The first power measurement tests means that a standard incandescent bulb uses 5 times as many amps as the Cointaker LED. They produce way more heat and still only half the light output.

Going LED is sure to decrease heat in the cabinet and go softer on the low-grade connectors found in almost all pinball machines. This will also make the boards run cooler. Not to mention mylar lifting above the insert due to the heat creating gasses from the plastic – which in turn will decrease the size of the insert, which will cause it to sink into the playfield.

I have been entertained watching the slow change in pinball-fans. It started out with them never wanting LEDs in their machines. Then it went to “inserts are OK, but not GI”. Guess where it is going next. Yes, the GI as well. Move faster, pinball-fans! You of all people should push for better tech!

There are no valid reasons not to use LEDs!

/Nicholas