Will it work on AC pump?

alexwai · 07-29-2004, 10:07 PM

Hi guys

After spending time in searching several forums, I realize that DC pump can be adjusted its performacne by changing the supplying voltage. My question is: Can I do the same thing on AC pump. Will there be any damange on it? Can all of you tell me the Pros and Cons on doing that? I got my Iwaki MD-20RZ pump and want to try if it is possible to do that.

Thanks

DrMemory · 07-29-2004, 10:24 PM

You can't change the speed of an AC motor by changing the voltage. When the voltage gets low enough the motor will simply stop. I'm not sure at what percentage below normal operating voltage where this will happen but it's not a lot.

AngryAlpaca · 07-29-2004, 10:39 PM

You can lower the motor speed with a fan controller (ceiling fan) or some such thing. I'm not sure about increasing it, but you can lower it...

lolito_fr · 07-30-2004, 03:36 AM

Have you tried this AA?
AC pump motors and fan motors are not the same design! Mag drive pump motors are synchronous - ie they are locked in to mains frequency. Lower the voltage and they will stall, not slow down...

Butcher · 07-30-2004, 05:38 AM

How to slow down an AC pump - make your own AC.

If it's something you really want to do you could hook up a variable frequency AC inverter and drive that off a DC source. It's not very efficient though - much easier to just get a DC pump.

funbun · 07-30-2004, 06:46 AM

or just buy a smaller pump

alexwai · 07-30-2004, 06:49 AM

Quote:

Originally Posted by Butcher

How to slow down an AC pump - make your own AC.

If it's something you really want to do you could hook up a variable frequency AC inverter and drive that off a DC source. It's not very efficient though - much easier to just get a DC pump.

Just hooking up the variable frequency AC inverter? Simple enough. My father-in-law got one spare frequency AC inverter. Think can get it with free. I guess it is now efficient, right.

Butcher · 07-30-2004, 07:06 AM

AC->DC->AC is not very efficient at all, too many conversions.
Note, cost to buy/aquire has no bearing on efficiency.

funbun · 07-30-2004, 07:26 AM

Why is my sig so big? I've got it on the lowest size and it's bigger than everyone else's

Butcher · 07-30-2004, 07:31 AM

Quote:

Originally Posted by funbun

Why is my sig so big? I've got it on the lowest size and it's bigger than everyone else's

Because it's full of crap?

Seriously though, use less lines if you want a smaller sig - really no one much cares about having system specs listed in minute detail, if at all.

alexwai · 07-30-2004, 07:48 AM

Quote:

Originally Posted by Butcher

AC->DC->AC is not very efficient at all, too many conversions.
Note, cost to buy/aquire has no bearing on efficiency.

Sorry for different definition on term "efficiency" .

I thought at the very first that frequency AC inverter = frequency transformer. After talking with my father-in-law, it is different. BTW, Is it OK to use the frequency transformer to do that job?

Butcher · 07-30-2004, 08:23 AM

Quote:

Originally Posted by alexwai

I thought at the very first that frequency AC inverter = frequency transformer. After talking with my father-in-law, it is different. BTW, Is it OK to use the frequency transformer to do that job?

Yes you can use a frequency converter. Also note that converting to frequencies much outside the 50-60Hz range (especially higher frequencies) may cause the pump to fail and will possibly invalidate your warranty.

funbun · 07-30-2004, 08:40 AM

I cut out a lot of stuff but the font size is still bigger than everyone else's. Maybe it's just the font size. I've got it set tp 120dpi in ATI cp.

redleader · 07-30-2004, 10:46 AM

This forum has sigs ?

07-29-2004, 10:07 PM	#1
alexwai Cooling Neophyte Join Date: Nov 2003 Location: Hong Kong Posts: 81	Will it work on AC pump? Hi guys After spending time in searching several forums, I realize that DC pump can be adjusted its performacne by changing the supplying voltage. My question is: Can I do the same thing on AC pump. Will there be any damange on it? Can all of you tell me the Pros and Cons on doing that? I got my Iwaki MD-20RZ pump and want to try if it is possible to do that. Thanks

07-30-2004, 05:38 AM	#5
Butcher Thermophile Join Date: May 2001 Location: UK Posts: 1,064	How to slow down an AC pump - make your own AC. If it's something you really want to do you could hook up a variable frequency AC inverter and drive that off a DC source. It's not very efficient though - much easier to just get a DC pump. __________________ Once upon a time, in a land far far away...

07-30-2004, 06:46 AM	#6
funbun Cooling Neophyte Join Date: May 2004 Location: Tuscaloosa, AL Posts: 53	or just buy a smaller pump __________________ SYSTEM: A64 3000+ @2.42Ghz w/CO stepping \| Chaintech VNF3-250 \| Sapphire 9600 Pro \| 2x512MB Corsair PC3200 \| Enermax 460w PS \| 2x80 gig IDE HD \| WATER COOLING: DangerDen Maze 4 CPU waterblock \| Hydor L20 waterpump \|Homemade reservior \| Heater core\| biketour.blogspot.com

07-30-2004, 07:06 AM	#8
Butcher Thermophile Join Date: May 2001 Location: UK Posts: 1,064	AC->DC->AC is not very efficient at all, too many conversions. Note, cost to buy/aquire has no bearing on efficiency. __________________ Once upon a time, in a land far far away...

07-30-2004, 07:26 AM	#9
funbun Cooling Neophyte Join Date: May 2004 Location: Tuscaloosa, AL Posts: 53	Why is my sig so big? I've got it on the lowest size and it's bigger than everyone else's __________________ SYSTEM: A64 3000+ @2.42Ghz w/CO stepping \| Chaintech VNF3-250 \| Sapphire 9600 Pro \| 2x512MB Corsair PC3200 \| Enermax 460w PS \| 2x80 gig IDE HD \| WATER COOLING: DangerDen Maze 4 CPU waterblock \| Hydor L20 waterpump \|Homemade reservior \| Heater core\| biketour.blogspot.com

07-29-2004, 10:24 PM	#2
DrMemory Cooling Savant Join Date: Jun 2004 Location: Dallas, TX Posts: 101	You can't change the speed of an AC motor by changing the voltage. When the voltage gets low enough the motor will simply stop. I'm not sure at what percentage below normal operating voltage where this will happen but it's not a lot.

07-29-2004, 10:39 PM	#3
AngryAlpaca Cooling Savant Join Date: Jan 2004 Location: Alberta Posts: 631	You can lower the motor speed with a fan controller (ceiling fan) or some such thing. I'm not sure about increasing it, but you can lower it...

07-30-2004, 03:36 AM	#4
lolito_fr Cooling Savant Join Date: Dec 2003 Location: France Posts: 291	Have you tried this AA? AC pump motors and fan motors are not the same design! Mag drive pump motors are synchronous - ie they are locked in to mains frequency. Lower the voltage and they will stall, not slow down...

07-30-2004, 08:40 AM	#13
funbun Cooling Neophyte Join Date: May 2004 Location: Tuscaloosa, AL Posts: 53	I cut out a lot of stuff but the font size is still bigger than everyone else's. Maybe it's just the font size. I've got it set tp 120dpi in ATI cp. __________________ SYSTEM: A64 3000+ @2.42Ghz w/CO stepping \| Chaintech VNF3-250 \| Sapphire 9600 Pro \| 2x512MB Corsair PC3200 \| Enermax 460w PS \| 2x80 gig IDE HD \| WATER COOLING: DangerDen Maze 4 CPU waterblock \| Hydor L20 waterpump \|Homemade reservior \| Heater core\| biketour.blogspot.com

07-30-2004, 10:46 AM	#14
redleader Thermophile Join Date: Jun 2001 Location: The deserts of Tucson, Az Posts: 1,264	This forum has sigs ?

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