Undervolt DDC 3.2

WeeMaan · 10-05-2009, 06:51 AM

Hello!
I'm sick of the noise my DDC 3.2 is producing, so the way I see it I have 2 choices.
Undervolt it or mod it to a DDC 3.1.
Undervolting it would be the easiest and most practical choice, because I don't have to take my loop apart and then I can adjust the voltage back to 12v when I'm benching.

Because if I have understod everything correct then the only difference between DDC 3.1 and 3.2 is the rpm?
At what voltage is the rpm on the DDC 3.2 the same as on the 3.1?

I was thinking about adjusting it to 9v, but does it start reliably on that voltage?

Thanks // WeeMaan

BrokenArrow · 10-05-2009, 09:29 AM

Before you start undervolting, check your foundation for which you have the pump mounted. Most noise from DDCs come from case vibrations and such.

If possible, hold the pump in your hand while running and if it is quiet, then it is the mounting that is creating the noise.

WeeMaan · 10-05-2009, 12:42 PM

Quote:

Originally Posted by BrokenArrow

Before you start undervolting, check your foundation for which you have the pump mounted. Most noise from DDCs come from case vibrations and such.

If possible, hold the pump in your hand while running and if it is quiet, then it is the mounting that is creating the noise.

It's not vibration, it's the actual pump noise.

millertime359 · 10-05-2009, 01:06 PM

IIRC, Martian tried running one a 7v but started to have issues with the pump. I have heard that guys have hooked them up to controllers like the BigNG and have been able to dial them back that way.

Mech0z · 10-05-2009, 01:14 PM

I have my 18 DDC connected to my Sunbeam Rhebus (None extreme) works wonders. I still find it abit noisy though compared to what I expected.

WeeMaan · 10-05-2009, 10:30 PM

Quote:

Originally Posted by millertime359

IIRC, Martian tried running one a 7v but started to have issues with the pump. I have heard that guys have hooked them up to controllers like the BigNG and have been able to dial them back that way.

What kind of issues?
Would that apply on 9v aswell?

Quote:

Originally Posted by Mech0z

I have my 18 DDC connected to my Sunbeam Rhebus (None extreme) works wonders. I still find it abit noisy though compared to what I expected.

At what voltage and rpm are you running it on?
Is it undervolted most of the time or are you just turning it down a notch or two when you want less noise?

I was thinking more like giving it 9v straight from the psu, would'nt that be possible?

Vapor · 10-05-2009, 10:53 PM

I use one of these: http://www.performance-pcs.com/catal...ducts_id=24692

7.7v to 12.5v range (yes, it overvolts)....never had a problem starting any of my DDC3.2s at minimum setting with it

WeeMaan · 10-05-2009, 11:03 PM

Quote:

Originally Posted by Vapor

I use one of these: http://www.performance-pcs.com/catal...ducts_id=24692

7.7v to 12.5v range (yes, it overvolts)....never had a problem starting any of my DDC3.2s at minimum setting with it

Great, if it starts reliably every time on 7,7v it would definetly not have a problem on 9v.
Next question then, how do you get it to take 9v from the molex directly from the psu?

fallwind · 10-05-2009, 11:13 PM

Only 2 ways to do it without using a controller: 1) use an inline resistor to lower the voltage or 2) make a custom power cable for your pump. One lead would go to a +12v source, the other lead would go to a +3.3v source. This would give a voltage of around 8.7v.

WeeMaan · 10-05-2009, 11:28 PM

Quote:

Originally Posted by fallwind

Only 2 ways to do it without using a controller: 1) use an inline resistor to lower the voltage or 2) make a custom power cable for your pump. One lead would go to a +12v source, the other lead would go to a +3.3v source. This would give a voltage of around 8.7v.

That sounds complicated, how would I connect the resistor?
And what kind of resistor do I need?
Or where can I get +3,3v from?

Perhaps I'll be better of buying a BigNG or simular.

Vapor · 10-05-2009, 11:35 PM

Quote:

Originally Posted by WeeMaan

Great, if it starts reliably every time on 7,7v it would definetly not have a problem on 9v.
Next question then, how do you get it to take 9v from the molex directly from the psu?

You'd have to use a SATA power connector (it has the 3.3V line on it, IIRC) and then make an adapter to have the 12V as the + line and 3.3V as the ground line. You'd get ~8.7V if it works

aspms* · 10-05-2009, 11:35 PM

Silence fan here as well- I had mine MPC355 running @ 7V (simple molex mod) for about 6months without any problems before I sold whole loop!

WeeMaan · 10-05-2009, 11:45 PM

Quote:

Originally Posted by aspms*

Silence fan here as well- I had mine MPC355 running @ 7V (simple molex mod) for about 6months without any problems before I sold whole loop!

Intresting! Because that would be much easier!

But I want the pump to be reliable, hate to have it die (or just not start on that voltage) on my and perhaps even taking some components with it.

Vapor - So how would I do that?
Would it be any easier with a resistor of some kind?
Something like in the link below? (I may be way off)
http://www.vekoy.com/product_info.php?products_id=2571

aspms* · 10-06-2009, 12:00 AM

and whats your argument why should it die running at lower voltage? If it starts normally and flow rate is enough for you than I see no problems at all!

imo less heat less chance to die!

WeeMaan · 10-06-2009, 02:25 AM

Quote:

Originally Posted by aspms*

and whats your argument why should it die running at lower voltage? If it starts normally and flow rate is enough for you than I see no problems at all!

imo less heat less chance to die!

Millertime 359 said that Martin had experienced issues when running it on lower voltage.
But I was more thinking of the fact that it may not start on lower voltage = may cause damage to components.

ecat · 10-06-2009, 03:45 AM

Quote:

Originally Posted by Vapor

You'd have to use a SATA power connector (it has the 3.3V line on it, IIRC) and then make an adapter to have the 12V as the + line and 3.3V as the ground line. You'd get ~8.7V if it works

The 3.3V line is certainly part of the SATA power connector specification but it is worth double checking if your connector actually carries 3.3V e.g. A standard 4 pin Molex to SATA adapter will only provide 5V and 12V, I suspect this is the case with most SATA power connectors even those connected directly to the PSU ?

WeeMaan · 10-06-2009, 10:39 AM

Are there more people running the DDC 3.2 on 7v here?
If so, please let me know how it's working for you, if it starts reliably and for how long!