12V vs 24V on Pumps

[Ghost]

I was wondering if anyone has ever tried to step up the voltage going into their pump.

 

It elevates and flattens out the pressure vs flow rate curve which means better performance.

 

You can buy converters for 12V DC to 24V DC with 90% efficiency on eBay for about £9 this being an example of one.

 

I am considering trying this just for experimenting purposes and fun but maybe someone has done it already.

 

______________________________

 

Before I confuse a lot of people with the graph let me explain what you are looking at:

 

The main pump used in water cooling this the 1/2 bar pump on the left hand side. You want to be looking at the very bottom right hand corner graph. There you can see the improvement the 24V does. It almost doubles the head pressure and almost doubles the flow rate.

 

 

 

It is important to note that the Laing D5 is rated to run at 8-24V. By running it at 12V you are actually under-volting it.

 

An actual interesting "non-help me" topic rarely comes up. That's why I made this. :/ Please reply and give your opinion or ask a question to keep this topic going.

 

Random fact; The D5 vario pumps full name is: "D5 Plastic DC Electronically  Commutated Spherical Motor Centrifugal Pump" :o

[Vitalius]

This is very informative. Awesome post. :D

Good to know for when I (eventually) go water cooling. 

[Ghost]

This is very informative. Awesome post. :D

Good to know for when I (eventually) go water cooling. 

 

As far as I know these are untested waters and no-one I know of has done this. Not something for an actual system, more for bench-marking. A cheap step up transformer like the one I posted from ebay will probably fail within a few months.

[JordanMac]

interesting read, rather than spending money the converter could you not just wire 2 molex together to add the 2 12v's together?

[VincentC]

Double the flow doesn't necessarily mean double the performance. Most people with d5 pump run them on the lowest setting (1), or d5 non-vario (4), and martinliquidlabs tests his items using (3).

[Ghost]

interesting read, rather than spending money the converter could you not just wire 2 molex together to add the 2 12v's together?

12V does not work like that afaik.

Double the flow doesn't necessarily mean double the performance. Most people with d5 pump run them on the lowest setting (1), or d5 non-vario (4), and martinliquidlabs tests his items using (3).

No way does it double the performance, all it would mean is the liquid would travel through twice as fast. This is also useful for people who need a higher head pressure because they have a much longer loop; maybe going outside the PC to and external radiator.

I think the fact that most people run their pumps at setting 1 is a testament to how overpowered the D5 pump is. Look at the curve for setting 1 vs setting 5 in the top right hand corner graph. That is technically all you need for a loop although I would feel more confident with setting 3. As long as the restriction in your loop is lower than when the curve hits the x axis at your setting then you are okay.

The interesting thing, however, is that going setting to setting you get 1C change on average, this would mean that you may get a significant performance increase of ~4C with 24V on setting 5.

[JordanMac]

if you wire 2 12V sources in series it would give you 24V, the problem is the current grounding through the PSU giving you 2 separate 12v circuits rather than 1 24v circuit. if that makes sense? you could always, if this is just a bench-marking thing, go 12v molex > 9v battery > aa battery > aa battery > pump > ground molex in series that would give you 24V for a short period of time. (as long as the batteries last)

[Ghost]

if you wire 2 12V sources in series it would give you 24V, the problem is the current grounding through the PSU giving you 2 separate 12v circuits rather than 1 24v circuit. if that makes sense? you could always, if this is just a bench-marking thing, go 12v molex > 9v battery > aa battery > aa battery > pump > ground molex in series that would give you 24V for a short period of time. (as long as the batteries last)

But if they are on the same rail isn't that just connecting 2 wires from the same source to the same thing. I don't know much about PSUs so I have no idea. How would you connect it in series.

[JordanMac]

But if they are on the same rail isn't that just connecting 2 wires from the same source to the same thing. I don't know much about PSUs so I have no idea. How would you connect it in series.

I think if you just connected 2 wires to the pump from the psu it would connect it p in parallel rather than series which would boost the amperage not the voltage. for the battery idea, positive to negative all the way round would be in series, basically what this does is take the 12v from the PSU and boost in with the 9v and 2x 1.5v from the batteries.

[Ghost]

I think if you just connected 2 wires to the pump from the psu it would connect it p in parallel rather than series which would boost the amperage not the voltage. for the battery idea, positive to negative all the way round would be in series, basically what this does is take the 12v from the PSU and boost in with the 9v and 2x 1.5v from the batteries.

I've probably got a variable power supply hanging around somewhere, I could probably use that if I find it and it can supply 24V. If not I could get a cheap step up transformer. I saw cheaper ones for £3 on ebay including shipping.

[JordanMac]

I've probably got a variable power supply hanging around somewhere, I could probably use that if I find it and it can supply 24V. If not I could get a cheap step up transformer. I saw cheaper ones for £3 on ebay including shipping.

yeah give it a go i'm interested to see some benchmarks for temps, i may do some myself if i can find the time.

[Ghost]

A small update to this thread.

 

I found this: http://koolance.com/ctr-spd1224-pump-or-fan-speed-controller

 

It accepts a 12V input.

[airdeano]

at some point you have the coolant flowing through the radiator too fast and thermal

transfer efficiency starts to deteriorate. when we were racing cars, we'd put on hi-flo

pumps to be able to slow the parasitic drag off the crankshaft. problem was we sped

the flow and the engine got hotter. so we put a high temperature thermostat and the

temperatures came down!?! because the coolant was moving too fast to allow the

radiator to absorb the heat from the coolant.

 

airdeano

[Ghost]

.

Would 1 D5 at 24V be likely move the fluid too fast? At any rate you can control the voltage on that koolance thing I linked above so you could always turn it down to a sweet spot. But you make a good point.

[airdeano]

yes, you can under-volt (silly to say when at 24v) and find that "sweet-spot".

also can use to tune for temperatures depending on radiator construction

and specs.

 

one thing i found out using 16v was that i did notice a bit more heat from the pump.

i'm figuring the heat is from a pressure plateau. a system will flow only as well as

most restrictive part/parts. not running any pressure gauges or flow meters, just a

laser temperature gun. jacking more "pressure" into the loop and no more flow is

exaggerated feels like the pump is almost dead heading. but i did not get to test

with more other radiators (Alphacool/SR1), used BIX 360 and RX360.

 

the only usage for this type of need i'd think is if you are using an external radiator

with tubing at 10m up and 10m back.

 

airdeano

[Biggshoes]

airdeano is right. I have professional experience with very very large , closed loop Industrial coolers. with the exact same components as a closed loop pc cooling loop. something like 5k gallon res, 48, 2 horse power radiator fans a 50 horse power 1700 RPM pump ect.

 

there is a point when more flow, will cause the water to pick up less of the heat from the components, and actually raise your " cpu " temps ( or in my industrial experience water jacket temps). 

 

you can get very very in depth with this conversation, but to keep it simple. more pressure from your pump, does not always mean better cooling performance, more flow from your pump also does not mean better  cooling performance.

 

can your increase your performance, by running a pump at a higher RPM ( this is what is going to happen if you run this pump from 12vdc, to 24vdc) maybe, can u decrease the performance by doing the same thing, maybe.

 

 

if you really want to try this, and you are looking for a quality Power supply (not a transformer as this is only for AC voltage conversion) there is a company called SOLA, that makes very high quality adjustable vdc power supply. 18 vdc-27 vdc, or 9 vdc -14 vdc. 

 

feel free to send me a PM, if you really want to dig into this in more detail.

[Parkway Drive]

I was looking at this for my dual MCP655 but decided on keeping it at 12V. Not sure if it will change the longevity of the motor if I went to a 24V so for peace of mind I just kept em 12V max not to mention I keep my pumps on lowest speed most of the time.

 

http://www.pccasegear.com/index.php?main_page=product_info&cPath=207_160_1285&products_id=17858