Measured actual electrical on my tank

fkshiu · #1 09-29-2008, 05:12 AM

So I picked up one of those Kill-a-Watt things from Crappy Tire and measured a bunch of stuff on the display tank and QT and here's what I came up with:

1. Eheim 1260 return (listed: 65w / measured: 53w)
Consistent with other results I've seen. Eheim 1260/1262s are underrated in terms of performance but overrated in terms of electrical usage.

2. Tunze 240/3 skimmer (listed: 45w / measured: 47w)
It is essentially a 6100 Stream turned into a venturi skimmer motor.

3. Tunze Wavebox w/6000 transformer (listed: 20w / measured: 15w peak)
The 20w number is for when the pump is being used as a 6000 Stream which may explain the difference.

4. Tunze Stream 6100 (listed: 45w / measured: 50w peak)

5. Tunze 6055 (listed: 18w / measured: 14w peak)

6. Tunze Osmolator (listed: 9 volts / measured: 10w peak)

7. Sureflow modded MJ900 (listed: 10w / measured: 8.5w)

8. AquaUV 2000+ (listed: 15w / measured: 15w)

9. Eheim 1048 CaRx recirc (listed: 10w / measured: 10w)

10. Dual M80 250w HQI MH ballast w/XM10K SE bulbs (expected: 748w / measured: 810w)
That's a LOT of power. The "expected" wattage is what Sanjay Joshi measured for one of the same bulb with the same ballast multiplied by 2.

11. Dual 80w T5HO on Workhorse7 ballast w/G-man actinic+ bulbs (listed: 160w / measured: 163w)
I should try an Icecap 660 to see how much it overdrives the bulbs.

12. Dual 160w VHO on PFO ballast w/UVL super actinic bulbs (listed: 320w / measured: 310w)

13. 23w spiral CF sump light (listed: 23w / measured: 22w)

14. 28w PC sump light (listed: 28w / measured: 20w)
I've noticed this light getting dimmer. It's on an old (+12 yr) Coralife ballast.

15. 3x 1w LED moonlights (listed: 3w / measured: 7w)

spreerider · #2 09-29-2008, 05:30 AM

in design everything should be overrated as it will only be at max power when its working at its designed max, if it is above max it means it is working harder than it was ment for, so it probably needs cleaning or was measured with a more acutrate device,
I can see this being true on some of the lower wattage devices as your meter is probably best at reading higher readings, like a digi voltmeter isnt very accurate at milivolts but is far more acurate around 120V because that is where its main use is and was calibrated for that level.

Delphinus · #3 09-29-2008, 05:09 PM

Wow. I'm blown away by the 810w reading for 2-250W lights.

Everything else looks pretty good though! But yeah, ... wow. Paying 810w to get 500w of light? It sounds terrible.

sphelps · #4 09-29-2008, 05:40 PM

might be worth while switching your halide ballast to electronic. I would imagine the HQIs are running pretty hot and at very low efficiency at that wattage.

With pumps the rated wattage should actually aways be higher than the steady state. Reason being is the pump will use a more power during start up, using the proper rating allows you to plan your electrical configuration properly to avoid tripping breakers and overloading circuits. However many companies are now rating there pumps at steady state to give the appearance of higher efficiency, in fact I would bet you're actually getting higher peaks than you observed, the device you used simply isn't fast enough to pick them up.

spreerider · #5 09-30-2008, 05:02 AM

wow thats really bad efficiency on the lights, your only getting 61% efficiency, most MH ballasts are rated at 80%-97% efficient i would be concerned with this and proably retest the lights then try one at a time, seems like your ballast is not operating properly and could be headed for a burnout (definatly the extra heat would not be helping,
Also i would take my bulbs out and put them back in, check for corrosion on connections, and redo all electrical connections as they could be poor and forcing the ballast to pull more amps.

fkshiu · #6 09-30-2008, 05:28 AM

Yeah, it's an old "industrial" M80 ballast. I'll double-check everything, but it might be on its last legs. I wonder if it could be a capacitor issue?

marie · #7 09-30-2008, 05:47 AM

I have no idea exactly how bright your lights are but mine with the hqi ballasts and SE bulbs I am easily getting twice the light that I was getting with DE bulbs.
I expect there to be more watts used and the bulbs to be overdriven (no matter what stircrazy says)

marie · #8 09-30-2008, 06:27 AM

Info taken from sanjays site comparing a 250w SE xm bulb and a hqi ballast with a 400w SE bulb and an ordinary m59 ballast

ppfd of the 250w is 182 and the ppfd of the 400w is only 172. Your getting more light out of your 250w ballast then you would from a 400w ballast

Delphinus · #9 09-30-2008, 04:58 PM

I guess the real question is what are the real watts out of a 400W? It's like the 250W M80 is more like a "real" 400W. Looking at Sanjay's site ( http://www.manhattanreefs.com/lighting ) I note that switching to an electronic ballast for 250W the XM lamps drops to 115.

Assuming an electronic ballast really uses 250W (might be a stretch, I don't know), and we get 115 ppfd, that's like saying 0.46 ppfd per watt. If the HQI uses 405W but nets 182 ppfd, that's also 0.45 ppfd per watt, but we just "get more".

So I guess it's not a real question of who's more efficient, but a question of how much PPFD do you want.

Wow, my head is swimming just trying to digest this. I knew that a 175W wasn't really 175 and 250W wasn't really 250 and 400W not 400W but I thought the "real versus rated" differences would be less than this.

Dang maybe T5's really are the way to go in the future.

fkshiu · #10 09-30-2008, 08:21 PM

Quote:

Originally Posted by Delphinus

I guess the real question is what are the real watts out of a 400W? It's like the 250W M80 is more like a "real" 400W. Looking at Sanjay's site ( http://www.manhattanreefs.com/lighting ) I note that switching to an electronic ballast for 250W the XM lamps drops to 115.

Assuming an electronic ballast really uses 250W (might be a stretch, I don't know), and we get 115 ppfd, that's like saying 0.46 ppfd per watt. If the HQI uses 405W but nets 182 ppfd, that's also 0.45 ppfd per watt, but we just "get more".

So I guess it's not a real question of who's more efficient, but a question of how much PPFD do you want.

Wow, my head is swimming just trying to digest this. I knew that a 175W wasn't really 175 and 250W wasn't really 250 and 400W not 400W but I thought the "real versus rated" differences would be less than this.

Dang maybe T5's really are the way to go in the future.

I think your conclusion is quite correct if you look at Sanjay's results across the board - the more juice you put in, the more light you get out of it. Of course the law of diminishing returns kicks in at some point where the extra PPFD isn't worth the added electrical cost. What concerns me is that my M80 ballast seems to be pulling quite a bit more than what Sanjay's M80 was pulling with the same bulb. I don't have a PAR meter to see how much useable light it is putting out, but sphelp's and speerider's concerns are well taken. The bulbs are CRAZY bright, for the record. I had a friend comment that you can't look directly AT THE TANK (not the lights) for a extended period of time without having to squint.

As far as T5s are concerned, putting them on an Icecap 660 ballast will overdrive them resulting in more PPFD, but at the expense of reduced lifespan.

I chose this particular MH combo because of the crazy PAR. My next set of bulbs (assuming that I don't change ballasts) will be Radium 20Ks which are spec'd to be driven by an HQI ballast. I'm curious as to what wattage results I'll get from them.