48V T8 Ballasts

[kitestrings]

Greetings.  Seasons greetings actually.

I'm wondering if anyone on the board has had any experience with these 48V ballast, or other products from this source?  Kind of interesting minimal signal control capabilities.

http://www.nextekpower.com/prod-ballast.html

-kitestrings

[scottsAI]

Hello kitestrings,

I have not used these ballast. Food for thought:

Ballast factor is 0.88 or 88% efficient. At $21 each + shipping.

If only one lamp then it would be a good solution.

If more than one a cheap inverter at $25 and two or more shop lights from Home depot at $8.50 is less money. Efficiency is not as good. Electronic ballast is 86 to 92%, lets use 89% for the calculations. Inverter is 90% for the energy with a quiescent current cost added, my 300w used 160ma with no load.

Your decision is based on lowest cost for reasonably efficiency or efficiency at any cost?

If 48v is your only good choice than the ballast my be the best over all solution. Not to many small 48v inverters around!

I helped design a hunting lodge power system. One very small inverter on the entry way CFL (40w on eBay for $6) Once in turn on the 300w inverter powering rest of the system. Well is 12v motor.

Battery is two golf cart batteries, 45w solar panel. (Harbor freight tools $200).

My first try at the $6 inverter did not work, was only 5w unit, not 40w it claimed. Will try again with another different inverter.

Have fun,

Scott.

[kitestrings]

Scott,

Thanks for your response.  You raise some valid points.

It probably stems more from my earliest AE experiences, and less from that of the better quality inverters available now, but I have difficulty relying on them exclusively for the necessities (light and water).  Having one down for repairs, no matter how infrequent, is a major pain.  I'd also assumed that a lightly-loaded larger inverter was likely well below acceptable efficiencies, but I hadn't considered multiple, smaller units.  Interesting.

I've always tended to run as many things directly off the batteries as possible; for efficiency and reliability.  Admittedly, this sometimes comes at higher cost.  I would have probably chosen a 12V CFL for your lodge/entry.

I have quite a few tube fixtures (got'em free), oddly with no ballasts, so I was thinking $21 was about normal for either standard or a 48V ballast, but some of prices you're finding are noteworthy.  A $6 inverter is a hard deal to beat.

-kitestrings

[ghurd]

Notice he said the $6 inverter "was only 5w unit, not 40w it claimed".

And "Will try again with another different inverter" means the $6 was wasted.

[scottsAI]

Ghurd, kitestrings,

Yes and No.

I bought item 370001627795 for $5.97, claimed 40w, was not. Many of them out there making this same claim. Not a big loss, annoying. At $1 unit cost I cant spend the time to return it with shipping cost. Then Bought item 220185007806 for $11.03, 100w inverter, Works great. Loaded it up with two 23 watt CFL for 45 minuets, inverter slightly warm. Lamps were as bright as two line powered next to them. (I could not see any difference). I like this unit, would be good for a laptop also, added versatility!

Waiting for item 190185624443, two 75 watt inverts for $13, what a deal! $6.50 each.

I plan to take some numbers and report, this has been coming up frequently enough.

The above deals are very repeatable

The last two are cheaper than the $20 cost of the 12v CFL, efficiency is close, the single CFL on the 100w inverter was 20.6watts, 18watts from line powered. I do not have a 20 watt or 12v CFL to compare it too. The ballast (linked in first post) reported 88% efficiency, looks like the resulting numbers may be close.

I need to redo the my test, can't find the package the 20w CFL came in, the bulb does not make any claims of lumen's, needed info to make an accurate comparison.

Looking over the numbers, maybe the 12v CFL might be a watt less power for the same brightness. For the cost difference the inverter offers many options. Long term cost are much cheaper for the $2 CFL + $7 inverter, after the first bulb replacement it represents a huge savings.

The assumptions are the $7 inverters are going to last. My guess is if they do not get hot, they might be the best deal.

The Fluorescent efficiency goes up as the bulb size goes up, two 11w will not equal brightness of one 20w bulb. Going to 32w T8 should improve things even more. T8 are more efficient then the T12.

I need to get a new shop light from Home depot, when I went the parking lot was full, not that desperate to find out about this!

Have fun,

Scott.

[ghurd]

A friend opened up a couple of the little $0.01 style inverters. 60~75W and 95~100W???

They were the same except the larger inverter had a bigger heat sink.

He was going to operate on the case with a Dremmel and put in a giant heat sink.  Not sure if he did.

I had a 60W? Vector and a 100~110W? B&D apart in a couple weeks.  Looked 100% the same (from memory), except the B&D had larger heat sink and a mini muffin fan.

My luck with those tiny plug-in inverters has been really REALLY bad.  Maybe a 10 cent heat sink would change my luck.

G-

[scottsAI]

Ghurd,

After testing, will disassemble one of the 75w units.

I have many inverters, 150, 300, 1000, 2000w opened all up.

Looks like multiple sections of 250w to get their wattage rating. The units below 250w have smaller transformers. I operate most below half rating, except for starting currents.

Only one unit is Good, Tripp-Lite 1000w, rated for 2000w for 5 minutes. I would feel OK about fully loading it.

Have fun,

Scott.