Quote:
Good luck. I spent the better part of a month last spring trying to kick up a couple of the DC motors for the MD/WMD line. It's either a hundred motor minimum order, or you try to piggy-back on some other companys order (hardly ever). But if you can find a source, give me a PM. |
Quote:
I really liked the sound (no pun intended) of this March pump. The manufacturers website referred me to a local dealer in CA. Ryan-Herco. I called them today and was told the pump is available, but the list price is 198(US) + tax + shipping! Ouch!! I puchased a muffled Laing D4 August 18 which is still within the 30 return window from Danger Den. I havent hooked the pump up yet but I am concerned I am not going to be too thrilled with the noise, even with a rheostat when not fraggin. It seems that any info on the noise levels of the muffled version of the D4 is either vague or measured in ways that cannot be directly compared to other pumps. It's too bad your article will probably be after my 30 day return has lapsed, because it looks like it will be a good one. Why is it you search and research and search some more, finally make an agonizing decision on which product comes the closest to what you want, and then after it's too late, something better comes along? |
that's a very interesting pump.
but if you want to talk price per year i think the csp 750 has it beat (assuming the 50k rating holds) at 7.4 USD a year (~5 years). Of course the p-q is not nearly as impressive, but not everyone needs that powerful of a pump. |
Hansfragger,
I bought the pump from http://www.depcopump.com/ which are located in Florida. Pump cost $125US (inclusive of tax) + postage. A little pricey in comparison to the other 12v pumps around, but again, over 5 years really quite cheap so long as the wetted end lasts that long. Really - it pays to shop around. $198 US + CA tax + postage is actually more expensive than what I could buy it for here in Australia. |
Quote:
In your opinion, how much quieter do you think it will be than the D4. The D4 is around 40+ DB at 12 volts. In comparison I have a Vantec Spectrum fan card in a pci slot blowing on my video card rated at 36.64 DB at 12V. It's noisy enough to be irritating if i'm not gaming. When turned down to 25 DB it's not bad at all. But you can really tell the difference on high. I don't mind losing the return shipping and 15 percent restocking fee if you feel the March pump will be substantially quieter. Thanks for the link- I owe you one. |
Sorry, I really wouldn't like to guess how loud it will be until I had one in my possession.
Of all the 12v pumps I've heard so far, the D4's are the loudest and most annoying, with the exception of pumps that used brushed motors - but nobody would buy one of these anyway for water-cooling use. The latest muffled D4's pretty much brings them in line with the rest of the brushless pack, but still not quiet, and still with an annoying (to my ear) whine. Most people who say that the muffled D4's are quiet tend to have a few 35dBA fans running at the same time (and are used to such noise), and for them the perception of "quiet" tends to mean quite a different thing to those who are after truly "whisper" quiet. |
Quote:
|
Thank you Cathar. What you said was exactly what I wanted to hear. The part I was concerned about was the whine. Many times the whine will end up grating on your nerves more than the overall noise level. I checked Depco's website and it states they are open M-Friday. I'm going to call them Monday. Things are looking up. Have a great one and thanks again!
|
Don't forget that they may have been clobbered by the latest hurricane - they're directly west of where it made landfall (about 150 miles).
The fact that their website is up doesn't mean their offices currently have electricity or phone service. So... if you don't get an answer Monday, give 'em a couple of days. |
Quote:
|
Pump arrived today. Very fast shipping.
Indeed it is a small thing. Including fittings and mounting tabs: 11.5cm long x 7.5cm high x 6cm wide. Will have a play with it sometime today as soon as my sick 4yo daughter stops pestering me every 5 minutes... |
A rather mediocre picture of the March pump next to a Swiftech MCP650:
http://www.employees.org/~slf/12v/m893-s650.jpg |
Can you be convinced to show us the impeller? (i.e. take the housing cover off?)
Your choice, of course... |
Think it would probably be best for him to do whatever tests he planned to do with it first before taking it apart and putting it back together, removes another variable.
|
i agree with bale.
plus it is a $125 pump, I'd be a bit hesitent about taking it apart. That does look like a very impressive pump though. |
Summary so far
This is a collection of posts I made over at OCAU:
Quote:
Quote:
Quote:
|
Well the pump is good, but it is not quite as strong as rated in pressure terms.
Static pressure head test at 12.00v is pretty much bang on 2.80m, which is quite a bit lower than the rated 3.20m pressure head. I've managed to develop a working PQ curve for the pump, which is not final, but will do until I finish more testing. I also tested at various voltages. To my total surprise the pump actually ran (and started) all the down to 2.80v, which is the lowest I was able to test at. Needless to say, the pressure here is absolutely pathetic, at around 0.09m of pressure head. Flow is a meek trickle that I didn't measure. I measured up to 14v, which is the peak recommended voltage for the electronics inside the pump. Here's the static pressure head chart. Pressures are rounded to the closest 5cm mark. 3.0v => 0.10m 4.0v => 0.22m 5.0v => 0.40m 6.0v => 0.65m 7.0v => 0.90m 8.0v => 1.20m 9.0v => 1.55m 10.0v => 1.95m 11.0v => 2.40m 12.0v => 2.80m 13.0v => 3.25m 13.5v => 3.45m 14.0v => 3.70m http://www.employees.org/~slf/curves/pumps/12vpumps.png |
interesting investigation
Thanks Cathar |
.5LPM difference between this and a 650 at cascadeload?
interesting even more so if price comes down. |
Quote:
With a 10W pump heat difference, and a radiator efficiency of, say, 0.03C/W, the actual difference at the CPU is likely to be zero. |
seems as though the march pump is suffering from its relatively "simple" impeller design?
|
Quote:
My impeller also seems to be slightly off-center, and I suspect that this is also the cause of the noise that I'm hearing. Tomorrow I'll be heading around to the local distributor to grab a new impeller and the 3/8" OD outlet housing. With two impellers, I'll look at hacking up a closed impeller modification to one of the impellers and see what difference that makes (if any). |
Picked up new impeller today, and the 3/8" outlet housing. Block's pressure has improved from quick testing. Need to investigate more. A little quieter too, but still somewhat rattly. Definitely an improvement. Perhaps the 3/8" config is the better option, and just step up to 1/2" outside of the block, rather than getting the 1/2" option by default.
|
Suspect the rattling is due to 1/2 turn of slack in the rotor/impeller coupling? (As seems to be typical on mag drives)
Must be a cure for that... |
Hey guys, I know March, and they make some damn fine pumps !
Pump choice is not easy, you have price, size, flow, EM, power use, replacement part costs, looks, etc to think about. But in my opinion, even though we are some what there competitor (not really given low PC liquid cooling numbers), that you should feel secure with one of there brushless units. :) Don't worry about them only rating the motor, there are SO MANY factors effecting pump life that it's almost impossible to predict for every application. "March has an impeller spinning on a shaft C-Systems has a steel shaft with a seal - both weak links if going for 5 yrs service" Sorry Bill, but must say something about this. First your right, both designs can fail. But a good designer considers there will be failures and what to do about it. Assuming even a Laing unit will not ever fail is wrong. One answer is monitoring, and low cost replacement parts. With AC pumps you have this now, as the impeller will make noise and a replacement is cheap. Not sure what cost of impeller is for the March unit, but would be nice if low. But the "ideal" solution is mag coupling, impeller speed monitoring, low costs, small size, cheap replacement parts, long lasting in fluid bearings,and low EM / power use /noise. But that pump does not exsist, and likley never will, well maybe with future superconductors :) |
All times are GMT -5. The time now is 09:24 AM. |
Powered by vBulletin® Version 3.7.4
Copyright ©2000 - 2025, Jelsoft Enterprises Ltd.
(C) 2005 ProCooling.com If we in some way offend you, insult you or your people, screw your mom, beat up your dad, or poop on your porch... we're sorry... we were probably really drunk... Oh and dont steal our content bitches! Don't give us a reason to pee in your open car window this summer...