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By tommyaleks
Hi guys, I need some help with my vacuum pump, I just bought a Vacuum Pump - 12V
ROB-10398 . here is the link for it....
My question is. does anyone know how to reduce the vacuum? like a vacuum regulator or something. is it possible to do that on this pump?

Another question is,, is it possible to make this pump to pulsate? Like draw the air and release.

if this is possible, can you tell me how I do this ?

Thank you all for helping me.

User avatar
By Ross Robotics
Just go down on voltage. You can also search for a circuit that can do what you describe. Maybe a FET controlled by something to make it turn off and on when desired.
By tommyaleks
Hm ok, So I can use a voltage regulator ? like a dimmer switch ? would this not be bad for the vacuum motor ?
By MichaelN
That looks like a standard brushed-DC motor, and PWM (Pulse-Width-Modulation) is a better way of controlling speed than just reducing the voltage.

Just pick your favorite microcontroller (eg Arduino), add a MOSFET and diode (to prevent back EMF voltage spikes) and you should be all set (after writing some simple code of course).
By Mee_n_Mac
Won't slowing the motor down just increase the time it takes to achieve 'vacuum' ? Now if the pump is fighting a noticeable leak, I can see such a scheme working as a 'vacuum regulator'. Otherwise a leak needs to be added ... and perhaps a pressure sensor if he wants a closed loop regulator.
User avatar
By Ross Robotics
Michael is correct. I didn't have the time to research the pump that SF sells. Now that I had some time, you are going to use PWM to achieve motor speed. Here is a good tutorial and wire diagram, You could use a different N-channel MOSFET, just make sure it's rated for your pump motor.

Mac has a point, if the motor's speed is say, ~50% of max, you may find that you don't have any vacuum. This is a diaphragm pump so it really depends on the quality. Read the comments on the product page, might give you some insight.
By MichaelN
codlink wrote:Here is a good tutorial and wire diagram, You could use a different N-channel MOSFET, just make sure it's rated for your pump motor.
You also want to make sure the MOSFET is rated for logic-level (5V) gate drive. Most are, but some like 10V or more on the gate to turn on properly.
By tommyaleks
Thank you all guys for you answers, this was great, Now I know a little bit more about this vacuum pump and what I can do to make this work. The link that was provided was just the right thing. My only concern now is if the pump are strong enough to make the vacuum drop or raise fast. if the pump uses (lot`s( of time to make the vacuum, this wont work. if the pump make the vacuum immediately you start it, this will be great. I have read what other say about this pump and they love it. did not say so mush about this subject but. I was also thinking about a manual vacuum gauge with a regulator but that is not pulsate. that only allow you to lower or raise the vacuum by hand. And that you mention codlink, if I must have full speed on the motor to get vacuum, then this wont work at all. but we will see. I will let you know how it went when I get the things I need.

And again, thank you all for your help.

By Mee_n_Mac
From the comments you should know that the 'vacuum' produced by this pump is only about 10 psi lower than ambient, or a bit over 4 psi, about the same as at the top of Mt Everest. How long it takes to get there will depend on the volume to be evacuated. This pressure sensor almost covers the pumps range (it bottoms out slightly before the pump does).
By ctfreak
Sorry to get this thread out again but I am really interested in buying this pump but have some really important questions to clarify first.

Does this pump work for vacuum purposes or does it also allow to be used as an air pump? I have a project in which I want to use it as an air pump to blow air into a baloon which should work in theory if this pump really has max. air pressure of 32psi.
Is this spec for air pressure or is it meant for the vacuum it can create?

Thanks in advance, I really hope that you could answer those questions.

By falingtrea
The data sheet specs both vacuum and pressure. Looks like it has two ports and shows a airflow direction, so I would say yes it can do both.
By ctfreak
Thanks so far for the answer but the problem is just from speculation I can't order this pump because I have limited time for the completion of my project only and it would be waste of money and time to order it and then see that it is not capable of being a normal air pump. There are other chinese vendors out there which have the pumps I need but if this pump would do, it would be the easiest and fastest solution to order one from sparkfun.
So could anyone who knows it exactly or even has one from this pump at home answer the question please ?

I would be very thankful if this gets clarified.
User avatar
By Ross Robotics
Read the datasheet, everything you need to know is in there. Falingtrea has already answered your question and you have enough time to write posts then you have enough time to read.
By ctfreak
codlink, what's your problem ? I already searched the whole forum plus read all comments on the product page on Sparkfun and tried to get as much information as I could get before posting here unlike many other newcomers to forums!
But unfortunately all one could find in these sources was speculation like posts from people who don't own this pump and say it must be capable of pumping air! So what's wrong with it when I just wanted to get info from someone who has tested this product ???
You could be more friendly to people like me!

Nevertheless, because I am a very friendly person, I wanted to say that indeed the pump is able to do all that which I found out by contacting the very good customer support from Sparkfun. Thumbs up for that. I ordered 2 of them and tested succesfully inflating a balloon. So for anyone else out there who has or will have the same question as I had, now they can find the answer in this forum by doing a search :)

By jremington
I already searched the whole forum plus read all comments on the product page on Sparkfun and tried to get as much information as I could get before posting here
No, you did not. Otherwise you would not have posted, as your question was answered several times by 1) the pump "data sheet" 2) this forum before you posted and 3) the comments on the Sparkfun product page.