Gravity feed pump question

[Enderman]

What speed will this pump be on with molex only?

https://shop.ekwb.com/ek-xtop-revo-d5-pwm-plexi-incl-pump

full speed

if you want to slow it down you need to plug it into a PWM header and control it

 

if you dont want to have it PWM controlled you should buy the D5 non-PWM version

[OddsCrazyStuff]

full speed

if you want to slow it down you need to plug it into a PWM header and control it

 

if you dont want to have it PWM controlled you should buy the D5 non-PWM version

Durring filling so will it run on molex only, so thats why I was asking.

[Enderman]

Durring filling so will it run on molex only, so thats why I was asking.

actually I just checked and the lain D5 will run at 60% speed without PWM while the EK D5 won't run at all

you will need a PWM fan controller for filling your loop, or a second PC to control the PWM pump

 

or just get the D5 that uses the little pot on the back instead of PWM, then you wont have this problem

[OddsCrazyStuff]

actually I just checked and the lain D5 will run at 60% speed without PWM while the EK D5 won't run at all

you will need a PWM fan controller for filling your loop, or a second PC to control the PWM pump

 

or just get the D5 that uses the little pot on the back instead of PWM, then you wont have this problem

Can you trick it with a 3 pin fan cable?

[Enderman]

Can you trick it with a 3 pin fan cable?

no

it needs a PWM signal

that's the 4th pin

[OddsCrazyStuff]

no

it needs a PWM signal

that's the 4th pin

Its kind of strange that it cant run on molex only.

[Enderman]

Its kind of strange that it cant run on molex only.

yeah

it seems like different brands of D5s do different things when not on PWM, according to everything I found on google

I would just play it safe and either give it PWM or buy a non-PWM pump

[OddsCrazyStuff]

yeah

it seems like different brands of D5s do different things when not on PWM, according to everything I found on google

I would just play it safe and either give it PWM or buy a non-PWM pump

Its kind of hard to give it PWM when the pc is off. Which is why I find it strange.

[AnonymousGuy]

Its kind of hard to give it PWM when the pc is off. Which is why I find it strange.

 

DC power is 100% duty cycle PWM.

[0ld_Chicken]

DC power is 100% duty cycle PWM.

with fans, yes. but not so with pumps.  My ddc 3.1 will run at about 50% with PWM unplugged.  I plug in PWM and it takes off wayyyy harder

edit: if that is what you were saying

[AnonymousGuy]

with fans, yes. but not so with pumps.  My ddc 3.1 will run at about 50% with PWM unplugged.  I plug in PWM and it takes off wayyyy harder

edit: if that is what you were saying

 

What I mean is you can just connect 12V (assuming that's the PWM voltage) to the PWM pin and it should run the pump full blast thinking it's 100% duty cycle.

[0ld_Chicken]

What I mean is you can just connect 12V (assuming that's the PWM voltage) to the PWM pin and it should run the pump full blast thinking it's 100% duty cycle.

oh I see.  I dunno about that (not saying you are wrong, just that I dont know) but I always thought that PWM was more controlled by the duty cycle of the signal, not the voltage

edit: seems like the more I read about PWM, the less I understand it lol.   not usually the case

[AnonymousGuy]

Electrical engineer here...I can roughly explain it:

 

duty cycle of 50% means that your signal is on 50% of the time and off 50% of the time.  If your clock frequency is 1 Hz, that means 50% duty cycle = 1 second (1Hz) on, 1 second (1Hz) off.

 

You can make the frequency whatever you want depending on how fast you want the on/off switches to happen, but the AVERAGE duration over a time interval is still the duty cycle.

 

If you have 100% duty cycle it means your signal never turns off which is the same as applying a straight DC voltage.

 

The amplitude of the voltage that your switching (aka pulse width modulating) doesn't matter (it's whatever you want it to be).

[OddsCrazyStuff]

So are we closer to an answer?