Digital Ballasts and comparisons in the end...

[Romeu9]

http://www.bghydro.com/BGH/static/articles/0506_digiballasts.asp

Digital Ballasts

The days of the old humming, magnetic core & coil-type ballasts may soon be coming to an end. The digital (electronic) ballast is the latest in ballast innovation. Digital ballasts are more efficient, quieter, cooler, and softer on the bulb. Digital ballasts do not have any of the usual transformers, capacitors or igniters; instead these ballasts have electronic circuitry to do the same job, more efficiently. What might take a standard coil/magnetic ballast 680-700 watts to fire a standard 600 watt bulb, may only take a digital ballast only 600-620 watts to fire the same bulb to the same brightness. The old coil type ballasts are hard starting ballasts; when the ballast fires the bulb it sends full power to the cold bulb. Over time, this shortens the bulb life and reduces the PAR output of the bulb. Digital ballasts start by sending a low amount of power to the bulb and steadily increases the power over the next few minutes until the bulb has reached full brightness. This is also known as soft starting, which minimizes the damage to the bulb and increases its PAR life (PAR represents the plant usable light; it’s what plants “see” and use, versus lumens which are what people see). After one year of use the plant usable light coming from bulbs that are run on digital ballasts has decreased only by 20-25% where as the same bulb being used in the coil type ballast would have lost 50-60% of its plant usable light over the same period of time.

Coil type ballasts are also known to cause the bulb to flicker or strobe. This takes place so quickly that the neither human eye nor light meter can pick it up. Digital ballasts provide a uniform power supply to the bulb, thus eliminating the flickering from the bulb.

A great feature of digital ballasts is the ability to run both MH and HPS bulbs on the same ballast without having to flip a switch (it should be noted that not all digital ballasts on the market are programmed (or optimized) to do this properly). Digital ballasts are “intelligent ballasts” and most are able to recognize the difference between the two types of bulbs and fire them accordingly. Because of the high starting power requirements of some bulbs (such as the Solarmax) digital ballasts cannot always fire these bulbs due to the soft starting feature inherent to digital ballasts. Nor do digital ballasts fire multi-vapor bulbs. The good news is that the majority of bulbs in our industry work just fine with digital ballasts. However, a great safety feature of digital ballasts also help to prolong the ballast’s life. If the bulb is defective or incompatible and does not fire, the ballast will only attempt to fire the bulb after a predetermined amount of time and shutdown if unsuccessful. Digital ballasts will also shut down if there is a short in the system. When purchasing a digital ballast, the consumer must be aware that there are a few “black sheep” in the digital ballast family. There are many inferior quality digital ballasts on the market; these manufacturers proclaim amazing power savings but don’t deliver. BetterGrow Hydro has looked at numerous digital ballasts over the past several years and we have settled on the Lumatek brand for specific reasons. Below are the results of our in store tests with various brands of ballasts. Gathering data was conducted using a wattage meter and a Hanna Light Meter, both of which are available to our customers should they wish to purchase these meters and run their own tests. The Hanna Light Meter was placed 29” from a Hortilux bulb and the lumen reading was taken once the bulb had reached and maintained full brightness. Here are the results from a few of our tests:

Results

*higher is better

*note: the 750W Lumatek was run at 220V; the amperage would have been almost double if it was possible to operate & test at 120V

*lower is better

*lower is better

Detailed Results

*lower is better

600w Lumatek (120v)

Watts: 610w - 620w

Amps: 5.1A - 5.15A

Light Output: 12.26

Efficiency: 50.6 (Watts/Light output)*

Time until full luminance: 2 minutes

Bulb: 600w HPS Hortilux @ 29"

600w Galaxy (120v)

Watts: 590w - 600w

Amps: 4.95A - 5A

Light Output: 9.71

Efficiency: 60.7 (Watts/Light output)*

Time until full luminance: 2 minutes

Bulb: 600w HPS Hortilux @ 29" (stopped firing bulb after 2 min on first attempt)

750w Lumatek (240v)

Watts: 750w (taken from ballast)

Amps: 3.38A (derived calculation)

Light Output: 14.9 (Power Source was 220v)

Efficiency: 50.3 (Watts/Light output)*

Time until full luminance: 3 minutes

Bulb: 750w HPS Super @ 29"

1000w Evolution (120v)

Watts: 1010w first 2 min - 850w after 4 min

Amps: 7.8A - 8.2A

Light Output: Peeks at 16.7 (2 min) then drops to 14.7 (4 min)

Efficiency: 57.8 (Watts/Light output)*

Time until full luminance: 2 - 4 minutes

Bulb: 1000w HPS Super @ 29"

Notes: Fan is louder than the humming of the SSX ballast!

1000w Sun System 6 (120v)

Watts: 1080w - 1100w

Amps: 9.6A

Light Output: 18.6

Efficiency: 59.1 (Watts/Light output)*

Time until full luminance: 6 minutes

Bulb: 1000w HPS Super @ 29"

An important aspect to note from the above results is that the digital ballasts that run on low power also emit less light. While this may help out with the power bill, it is disastrous for your plants. The actual efficiency of some of these ballasts is worse than the old coil ballasts.

Another observation was that the Galaxy ballast seems to have a problem firing a new bulb for the first time. After firing a new bulb for two minutes the ballast shuts down and stops firing the bulb. Once the ballast has fired the bulb for the first time, however, it is able to fire the bulb the second time and maintain the power to the bulb. The Galaxy was also the least efficient out of all the ballasts in converting electrical power into light; even the 1000w coil ballast was more efficient!

The 750w Lumatek ballast produced more light than 1000w Evolution; this was true even though the Lumatek ballast was powered by 220v and not the required 240v. We also found that the light intensity on the Evolution decreased further after 30 minutes of operation.

It should be noted that Hortilux bulbs (which we used for many of our tests), while having a good spectrum, have a relatively low lumen output. Had we used a standard bulb (such as a Philips or Sylvania) the output ratings undoubtedly would have been higher.

The last point we would like to make here is the fact that after 2-3 years of operation (sometimes less), coil ballasts begin to degrade in performance and generate even less light than when they were new; digital ballasts do not experience this decrease in performance.

RF Interference

The next test was to measure RF interference. To do this we first placed the ballast at four feet from our radio and gave a rating according to the amount of interference for both FM and AM radio stations. Then the ballast was then placed 30 feet from the radio and the same process was repeated. Our results are as follows

	4ft AM	4ft FM
600w Lumatek	Moderate Interference.	none
600w Galaxy	Extreme interference (Cannot hear radio transmission) when bulb fires (lasts about 30 seconds), Once bulbs has fired and the lamp is being maintained RF interference is High (Can hear radio broadcast but with considerable static).	none
750w Lumatek	Moderate Interference for 2-5 seconds while the ballast first fires bulb. No interference after bulb successfully fires.	none
1000w Evolution	Moderate Interference	none

	30ft AM	30ft FM
600w Lumatek	Slight interference (Radio broadcast is clear with a slight amount of interference in the background).	none
600w Galaxy	Slight interference (Radio broadcast is clear with a slight amount of interference in the background).	none
750w Lumatek	none	none
1000w Evolution	Slight interference (Radio broadcast is clear with a slight amount of interference in the background).	none

Customers should avoid all digital ballasts that do not have RF shielded lamp cords. The RF interference from these digital ballasts is substantial. If you do not see a metal shield between the outer coat and the wires on the inside of the lamp cord, the cord is not shielded. Digital ballasts do not interfere with FM radio stations but do cause static on AM stations. The better quality digital ballasts, such as the Lumatek, cause the least amount of interference. It should be noted here that the 750w Lumatek ballast we tested was of their latest revision. Ironically, this revision does not utilize an RF shielded lamp cord; Lumatek claims that this is due to internal changes made to the ballast that make the RF shielding unnecessary, and as you can see by the test results, it produced virtually no interference after the first few seconds. Lumatek claims that all of their ballasts will utilize this same construction in the near future.

[Jimmy]

Thanks amigo....

[Romeu9]

You're welcome guys, wen I found fine things for myself I always post them here, for everyone!

Take care

[Romeu9]

Lumatek is the winner!

750w Lumatek (240v)

Watts: 750w (taken from ballast)

Amps: 3.38A (derived calculation)

Light Output: 14.9 (Power Source was 220v)

Efficiency: 50.3 (Watts/Light output)*

Time until full luminance: 3 minutes

Bulb: 750w HPS Super @ 29"

take care

[Guest superbluehaze]

excellent post, my friend.

take care,

john

[Guest superbluehaze]

thank you RIx;

You are tight too.

Felicityb please post in the relevant sections;

I understand you are a gamer but you would be better off making this comment a separate post in the chat section.

I have del your comment, but you can if you wish post about Sony in the chat section.

I only use digital ballasts, and I have had to send back my 1000watt Lumatek ballast, but it was replaced;

take care,

john

[Guest superbluehaze]

I am sorry RIX, your comment went as well;

take care,

john

[Flail]

now to me it appears that ballists run most effeciantly at 220V, or is it that particular balist?

[Dust]

yeah it's hard to see the truth in all those comparaison ^^ best way to do it is to try it ourselves

still nice reading tho

[Romeu9]

I can also throw out links. Makes me wonder how much is sell talk and how much is real.

It was not like that, wen I drop links I drop good links.

Growers cant perform tests like this, I know what you mean but we grow, we dont perform tests of this kind do we?

This is was done by a shop, that also cares for good information.

They done it so the buyers could have some more info to check before buying.

It is what it is, glad you liked it at some point.

One's conclusions to each one too.

Take care