A question about pumps

[NanuNanu14]

I was looking at the pump I will be using for my custom loop, the Alphacool VPP655, and it raised a question in my mind.

 

There is a 4-pin Molex connector with 2 pins, and a PWM fan connector. Do I need both of them plugged in to run the pump, or is it an 'either/or' situation?

 

If there's someone who could explain this to a first-time water cooler, that would be wonderful.

[Skiiwee29]

The 4 pin Molex is what provides the actual power while the fan connector provides PWM control for the speed of the pump. If you didnt have this plugged in, your pump would run at 100% 100% of the time. 

[NanuNanu14]

Alright, thanks for that.

[xgn]

7 hours ago, legacy99 said:

The 4 pin Molex is what provides the actual power while the fan connector provides PWM control for the speed of the pump. If you didnt have this plugged in, your pump would run at 100% 100% of the time. 

Im doing that all the time. My pc see it as 4821rpm.

There is no drawbacks to it on my loop. Its same pump as OP is going to use.

[Skiiwee29]

8 hours ago, xgn said:

Im doing that all the time. My pc see it as 4821rpm.

There is no drawbacks to it on my loop. Its same pump as OP is going to use.

Its not good for the longevity of the pump. If you run something at 100% power/speed 100% of the time, its going to wear out alot faster than something you turn down during idle or low temp times. 

[0ld_Chicken]

21 hours ago, NanuNanu14 said:

I was looking at the pump I will be using for my custom loop, the Alphacool VPP655, and it raised a question in my mind.

 

There is a 4-pin Molex connector with 2 pins, and a PWM fan connector. Do I need both of them plugged in to run the pump, or is it an 'either/or' situation?

 

If there's someone who could explain this to a first-time water cooler, that would be wonderful.

Is the the vpp655 or the vpp655PWM?  Both have a "molex" connector for the PSU and a connector for the motherboard.  I'm assuming you have the PWM model with the TWO wires going to the motherboard connector?  Is there a red dial on the back?

 

I believe that the PWM model should actually start at 60% when not plugged into the motherboard.  Lots of people complain about this when it comes time to fill their loop and the pump will not push out 100% unless they turn ON their actual PC (instead of jumpering their PSU like most people do).  Some people have even made arduino PWM controllers just to run their D5/DDC PWM pumps at 100% while filling to avoid this problem. 

 

EK's NEW d5's will run 100% when not plugged into the mobo to fix this issue.  

 

That being said, running the pump at 100% should be fine for years.  D5's are 12v AND 24v pumps, so really running them at 100% @ 12v is nothing.

[airdeano]

6 hours ago, legacy99 said:

Its not good for the longevity of the pump. If you run something at 100% power/speed 100% of the time, its going to wear out alot faster than something you turn down during idle or low temp times. 

 

you do know that the laing D5 is rated for 50,000hrs (5.7 years running 24/7) MTBF (Mean Time Before Failure)

this is a failure test at 24v for 50,000hrs+ not at our 12v usages.

doubtful the pump will 'wear-out' from full speed operation.

 

actually, the lower the voltage, the warmer the pump will get. the pump is cooled from the coolant inside the pump top, pump impeller and impeller socket. the slower the flow rate the less the pump will stay cooler. the PWM function cures most of this as the nominal voltage is at full current and the PWM switching reduces the speed without overheating or improper low voltage operation.

[NanuNanu14]

@0ld_Chicken the pump is PWM, there's no red dial at the bottom.

 

Also, is it better to use a hub for the fans, or is a splitter cable better?

[0ld_Chicken]

3 hours ago, NanuNanu14 said:

@0ld_Chicken the pump is PWM, there's no red dial at the bottom.

 

Also, is it better to use a hub for the fans, or is a splitter cable better?

I believe it'll run at 60% with no mobo header plugged in.

 

Depends on the situation for splitter or hub.  If it is just a few, low power fans then a splitter is fine. If your hooking a lot up, or theyre high power pwm fans, you may want a hub with a external power source (molex or sata) so you don't burn out the mobo/fan controller

[NanuNanu14]

Right now, the current plan is to use a 3-way splitter cable with some TT Riing 12 fans on top, and a 2-way splitter and some undecided 120mm SP-optimized fans. Most likely 1500 rpm Vardars.

 

I don't expect any of those to pull a great deal of power at all.

 

EDIT: With people asking stuff like this, why isn't it in more videos, even if it's just done to idiot-proof something?

Edited September 13, 2016 by NanuNanu14
had something to add that wasn't worth a new post.

[0ld_Chicken]

9 hours ago, NanuNanu14 said:

Right now, the current plan is to use a 3-way splitter cable with some TT Riing 12 fans on top, and a 2-way splitter and some undecided 120mm SP-optimized fans. Most likely 1500 rpm Vardars.

 

I don't expect any of those to pull a great deal of power at all.

 

EDIT: With people asking stuff like this, why isn't it in more videos, even if it's just done to idiot-proof something?

Both of those sets of fans should be able to run off of their own fan header with no issues. Technically they could all be ran off one header.  2.4w per riing and .75w per f2-120 vardar being well under 12w=1a (start up power included) 

[NanuNanu14]

My Mobo is an ASUS X99-a/3.1. I don't have enough fan headers in the right places, to run each fan and the pump off their own header. Didn't want to risk running every fan off of 1 hub, so using two splitter cables felt like the better option.