Some Laing D5 Testing, 13.1-24V is the same

It took a little tinkering to finally get a decent setup. One problem with pump testing using a reservoir is you will have static pressure that changes as the reservoir emptys. Also this reservoirs added pressure can "help" the pump along if the outlet of the test loop doesn't match and it lower. A closed loop will not have that problem, but I also needed something that bleed really fast and has absolutely minimal inlet pressure losses, so a custom reservoir with 5/8" barbs and radius inlets was key.

Here is the loop on my test bench. And no this isn't in my bathroom sink, I have a long bench in my home office next to my computer where I spend alot of time tinkering..

Pump> Pressure test T > Flow Meter > Globe Valve > Reservoir >
http://www.overclock.net/gallery/dat.../Pump-D5-1.jpg

http://www.overclock.net/gallery/dat.../Pump-D5-2.jpg

Seems to work really well, with as minimal a pressure drop as possible. Also because my manometer is adjustable to zero, I can remove the static pressure that is on the testing T from the loop above..

So first up, how about a maximum pressure head test. No it's not the 11' noted in specs everywhere, closer to 13'..:yessir:
http://www.overclock.net/gallery/dat.../Pump-D5-3.jpg

And how about a maximum flow rate, note this still has 30+ inches of pressure due to the loop and flow rate meter, so it's not the pump maximum where pressure = 0, it's the maximum I can do with the pressure drop within the loop.
http://www.overclock.net/gallery/dat.../Pump-D5-4.jpg

And to get the full picture, here is the systematic test results incrementally that were needed to develop the full curve. The end results were slightly lower than Laing's own graph, but it has the same curvature, and it's higher than swiftech's.

Nothing too spectacular here, it's about what I expected for the stock top, more than anything I now have a good baseline to compare a custom top to. The DDC3.2 with Petra top according to Petra's testing is still superior at 12v in the higher pressure side of the curve (The D5 doesn't take the lead until 2.5+ GPM range). I'll post some more curves to compare things later...

http://www.overclock.net/gallery/dat.../Pump-D5-5.jpg

But what really had my curiosity was going over 12V. This is where things get interesting...

I chose to compare results of adjusting voltage while testing maximum flow rate. This produces the most extreme current draw from the pump and highest flow rate.

First up 12.0V nothing too special.
http://www.overclock.net/gallery/dat.../Pump-D5-6.jpg

Then I noticed something right off. While slowly turning up the voltage, the maximum and plateau begins right at about 13.1V. Anywhere from 13.1V to 24V produced the exact same performance. It's strange, I can actually turn it up a bit and see the flow rate go up, and a moment later it back down to the 13.1V performance.

I've heard there was circuitry in the pump, and apparently this was clearly working. Not sure if the circuit adjust by maximum RPM or something else, but you can very clearly see it react to the jump in voltage as it slows the pump right back down.

So this is the Limiter test...

THE MAXIMUM CURRENT DRAW
http://www.overclock.net/gallery/dat.../Pump-D5-7.jpg

Now....how about 24V volts....
http://www.overclock.net/gallery/dat.../Pump-D5-8.jpg

At first I was thinking heat dump was tied to Amperage, it's not.

As Fairydust pointed out below. Wattage is Voltage x Amperage which is about 28 to 29 watts for anything at or above 13.1V.

So in the end, nothing suprising here other than I can say the limit on gains is a dismal 13.1V. Probably not really worth it to run any sort of special PSU on the D5's then..:(

Update 11-20
After getting some great advise and looking around, I decided to record voltage and amperage relative to flow rate to make a "Watts used vs Flow Rate" curve.
This is the result:
http://www.overclock.net/gallery/data/500/Pump-D5-9.jpg

Another UPDATE

Stock top D5 at 24V
http://www.overclock.net/gallery/dat...Pump-D5-10.jpg

And the direct comparison of 12V vs 24V. With this, I can say I see no reason at all to run at anything over 12V. The performance between 12V and 24V is exactly the same where it matters in water cooling. It's not until beyond 2.5GPM that you even start seeing any gain with the 24V curve. Also 24V is typically using about an extra 1 watt of power.

http://www.overclock.net/gallery/dat...Pump-D5-11.jpg

Last Update, Testing Complete

Here is a summary graph of all 5 settings tested along with a 12V and 24V on setting 5. I guess the one thing that became more obvious for me was how "Variable" the power consumption is.

Setting one may only draw 3 watts, while setting 5 could be nearly 10X that amount. It's probably worthwhile on light heat loads or smaller radiator setups to try some of the lower settings. The lower heat dump of these lower settings may be more beneficial than the higher flow rates in very special cases.

Also it's very obvious, and I guess this is consistent with other pumps, but power consumption go up as flow rates are increase (less restriction).

http://img214.imageshack.us/img214/9507/pumpd512nf5.jpg

I'll plan on adding these into the estimator.

Great testing once again. But power draw at 13,1 V = 28,3 W , 24 V = 28,8 W, so I don't see the efficiency gain..

I ran my D5s on a 13,8 V PSU ever since the old Syystemcooling review,

Quote:

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Originally Posted by Fairydust

Great testing once again. But power draw at 13,1 V = 28,3 W , 24 V = 28,8 W, so I don't see the efficiency gain..

I ran my D5s on a 13,8 V PSU ever since the old Syystemcooling review,

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You're right, they are the same or close to it.

So I guess in conclusion there is no difference after about 13.1V..

Oh well, that make more sense :up:

I came up with even stranger conclusions at that time of night, no worries :p:

Quote:

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Originally Posted by Fairydust

I came up with even stranger conclusions at that time of night, no worries :p:

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Well I've corrected the title to something more appropriate. And I was all ready to go get that meanwell 24V PSU for my D5's...hehe.

I thought I found something. And I did, and that is I've been out of college so long I can't even remember basic electronics...:rofl:

Quick question...

Could there be an efficiency difference between the two voltages if the net result in watts is the same?

I would think no...?

Great bit of testing again even though the results didn’t turn out the way you expected. At least you’ve proved that it would be a waste of time investing in a Meanwell 24v psu.

When I was doing some tests on flow and using my D5 vario there was no improvement in flow between setting 4 & 5 on the pump. Have you any thoughts on this.

I have two pumps so I’m going to try the other one under the same condition to see if they both act the same.

Cloud I please ask you a couple of questions. I’ve just started doing some basic tests with my SF800 flowmeter and T-Balancer extension Sensor. I’ve got them working together, but something strange seems to be happening. When I turn the pump up the reading on the nav2 monitor L/ per min goes down instead of up. It’s as though it’s reading in reverse.

I know the output between the SF800 and the Sensor hub will be different, and I haven’t began to do any flow test with them yet, but I would have thought that if I turned the pump up the L/per min would go up instead of down.

If you have any thoughts on this I would very much appreciate your help.

Unfortunately I lack in so many areas that are needed to achieve the right results in this area.

I am looking forward to the tests you do with the SF800 because yours will be a lot more precise and the conclusion will be a lot more credible than mine.

When do you plan to carry out the tests on the SF800, and will you be using the T-Balancer Sensor hub as well?

Quote:

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Originally Posted by ladderman

Great bit of testing again even though the results didn’t turn out the way you expected. At least you’ve proved that it would be a waste of time investing in a Meanwell 24v psu.

When I was doing some tests on flow and using my D5 vario there was no improvement in flow between setting 4 & 5 on the pump. Have you any thoughts on this.

I have two pumps so I’m going to try the other one under the same condition to see if they both act the same.

Cloud I please ask you a couple of questions. I’ve just started doing some basic tests with my SF800 flowmeter and T-Balancer extension Sensor. I’ve got them working together, but something strange seems to be happening. When I turn the pump up the reading on the nav2 monitor L/ per min goes down instead of up. It’s as though it’s reading in reverse.

I know the output between the SF800 and the Sensor hub will be different, and I haven’t began to do any flow test with them yet, but I would have thought that if I turned the pump up the L/per min would go up instead of down.

If you have any thoughts on this I would very much appreciate your help.

Unfortunately I lack in so many areas that are needed to achieve the right results in this area.

I am looking forward to the tests you do with the SF800 because yours will be a lot more precise and the conclusion will be a lot more credible than mine.

When do you plan to carry out the tests on the SF800, and will you be using the T-Balancer Sensor hub as well?

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He will do this when he will receive mine. I'll contact Martinm210 for shipping infos as soon as I receive mine from Dirk.

Quote:

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Originally Posted by ladderman

Great bit of testing again even though the results didn’t turn out the way you expected. At least you’ve proved that it would be a waste of time investing in a Meanwell 24v psu.

When I was doing some tests on flow and using my D5 vario there was no improvement in flow between setting 4 & 5 on the pump. Have you any thoughts on this.

I have two pumps so I’m going to try the other one under the same condition to see if they both act the same.

Cloud I please ask you a couple of questions. I’ve just started doing some basic tests with my SF800 flowmeter and T-Balancer extension Sensor. I’ve got them working together, but something strange seems to be happening. When I turn the pump up the reading on the nav2 monitor L/ per min goes down instead of up. It’s as though it’s reading in reverse.

I know the output between the SF800 and the Sensor hub will be different, and I haven’t began to do any flow test with them yet, but I would have thought that if I turned the pump up the L/per min would go up instead of down.

If you have any thoughts on this I would very much appreciate your help.

Unfortunately I lack in so many areas that are needed to achieve the right results in this area.

I am looking forward to the tests you do with the SF800 because yours will be a lot more precise and the conclusion will be a lot more credible than mine.

When do you plan to carry out the tests on the SF800, and will you be using the T-Balancer Sensor hub as well?

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Yeah, I was a bit bummed that I didn't find out otherwise. Looks to me like the circuitry in the pump works as a speed or wattage limiter of sorts and kicks in at about 13.1V...oh well. I'll still run a 24V curve since it's setup.

As far as your setting 4 and 5, I suppose if you have enough restriction in a loop, the difference between 4 and 5 will be fairly small, perhaps difficult to measure. I'm thinking I'll run a curve at some of the settings too. I'd like to get a better handle on current draw at the lower settings too. It's been more than once that I've heard someone say a lower setting gave them better results, so heat dump must really start playing a role particularly in setups with smaller radiators.

I really don't know much about the electronics behind the SSF800. It would make sense to me that it would go up..:D Maybe someone on the boards with more electrical knowhow can comment?

And sorry about the pics going on an off line here, it looks like imageshack is struggling a bit this morning..:shrug:
I switched the pics over to a different server, lower quality, but at least they show.

Wattage curve created:
http://www.overclock.net/gallery/data/500/Pump-D5-9.jpg

Another UPDATE

Stock top D5 at 24V
http://www.overclock.net/gallery/dat...Pump-D5-10.jpg

12V vs 24V

I think this is pretty conclusive that 12V is the better option. No performance gain at all at 24V until past the range most water cooling systems run, and all while drawing a little more power.

http://www.overclock.net/gallery/dat...Pump-D5-11.jpg

Testing Complete
http://img214.imageshack.us/img214/9507/pumpd512nf5.jpg

Conformation of data is always welcome, even if it just backs up what we thought we knew...

Good job again Martin! Thanks for the report. :clap:

Quote:

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Originally Posted by Talonman

Conformation of data is always welcome, even if it just backs up what we thought we knew...

Good job again Martin! Thanks for the report. :clap:

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Thanks!

Yeah, I was kind of hoping there was some potential with high voltage, but I can't see any reason at all to use more than 12V with the stock top, almost identitical performance clear out to 2 GPM.

I also wanted to make the equations to update my flow rate estimator and include all of the settings.

I still need to make one more run with my basic model pump, but it should follow fairly closely to the setting 4 plot.

I guess more than anything I just wanted to finally make some runs with my new testing toys..they work very well..:D

Can you do the same with a DDC between 9w and 18w (just undervolt the 18w with something to control the voltage) ?

Quote:

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Originally Posted by Xilikon

Can you do the same with a DDC between 9w and 18w (just undervolt the 18w with something to control the voltage) ?

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I wish I had a DDC to test, but I only have 3 D5's (this stock variable, a modified top variable, and a modified top basic).

I will have some other blocks I'll be testing soon, but no DDC's on the way.

Alex has done alot of testing on the DDC's most of his results are on their site:
http://www.petrastechshop.com/laddcwpeddto.html

It looks like the DDC minimum starting voltage is 9V and it can run up to 13.2V.

It would be interesting to see a curve at 9V, 12V, and 13.2V. tested on the same setup for a direct comparison to the D5. I can run any voltage on my variable PSU from 0 to 30V, so not problem there.

And with the EK top??? :)

Quote:

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Originally Posted by Anemone

And with the EK top??? :)

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You'll have to ask EK for that. They have my results, and they are the only one that knows if these production copies match any of the prototypes I tested. Very possible they made some tweaks since then.

I always request permission before I post testing results, and I never got a response back on this one...sorry.

I do however have some updated stock D5 test results I did at the same time, they were using my new total dynamic head method of measuring inlet and outlet pressures, so I'll be updating the estimator with those results.:up:

Martin, don't know whether you can answer this, but can the second hole on the EK top be used to fit a fillport tube?

I absolutely respect your need to defer to EK. Silence, however, on the performance numbers which don't even appear on EK's site is not a good sign. But EK does do a really great job on so many things we'll have to wait and see.

What circuitry is limiting the RPM, and can it be skipped?

I think you could probably use one of the inlet side port for a fillport, but I'm not sure how well/if it would work as a T-line, maybe in combination with another reservoir would be fine.

Anyhow, don't let silence fool you. I was impressed and wouldn't be running it if it were otherwise.

Not sure on the circuitry, I'm an electornics greenhorn. I get all excited when I wire in a resistor for an LED, couldn't tell you on the IC chips or what's going on in there. I've been hopefull one of the electrical gurus in the forums would figure out how to make a step 6 or 7 out of the circuitry, but it's beyond my abilities.