Slow Down Pump RPMs

[rickangabi]

Does anyone have way to slow down the RPMs on a March pump. I have not been able to find a VFD (variable frequency drive) suitable for this pump.

Thanks for the help.
Rick

[ricand]

I'm not sure why you want to slow down the motor speed. If you want to slow down the volume it is pumping just put a ball valve on the output side. It won't hurt anything since it is a magnetically coupled.

[rickangabi]

The March pump spins at 3500 rpms which is beating the daylights out of the wort in any situation. While I am aware that adding a valve to the output of the pump is a common practice this would only compound the hypothetical problem. My goal is not to slow down the flow of wort. My goal is to reduce the chances of HSA and stress on the wort by slowing down the speed of the pump. My wort runs through a heat exchanger coil so there is already restriction on the pump.

[fossilsrocks]

If the impeller is spinning in just wort (Not lots of air) it couldn't have any effect on HSA. What do you mean by "Stress on the wort"?

[pclemon]

Stress on the wort? What can you possibly be stressing? Commercial breweries use pumps that would creat pressures FAR above what that little March pump creates.

[Brewtime]

The March pump spins at 3500 rpms which is beating the daylights out of the wort in any situation. While I am aware that adding a valve to the output of the pump is a common practice this would only compound the hypothetical problem. My goal is not to slow down the flow of wort. My goal is to reduce the chances of HSA and stress on the wort by slowing down the speed of the pump. My wort runs through a heat exchanger coil so there is already restriction on the pump.

HSA is not a factor in this scale and size I think you are thinking to much RDWHAHB

[BeerPal]

Stress on the wort? What can you possibly be stressing? Commercial breweries use pumps that would creat pressures FAR above what that little March pump creates.

HSA is not a factor in this scale and size I think you are thinking to much RDWHAHB

+1

Reinventing the wheel almost never works.

[Monster Mash]

A motor controller that won't destroy a march pump is very expensive and definately not worth the money. As long sa there is no air in the lines the spinning impeller will not have any effect on the wort at all.

[WingStall]

You're trying to solve a problem that doesn't exist in the first place.

1) HSA is a myth.

2) VFD's only work with 3-phase motors (I'm 99% certain)

3) a valve downstream of the pump is the ideal way to throttle flow on a March pump

The only time using a valve is bad is if you have your own brewery, you're stupid, the VFD for your 5hp brewhouse pump burns out and you're forced to throttle wort flow with valves, you accidentally route the wort to a section of the manifold that is necked down to 1" and is disassembled for maintenance, and you get a 100gal/min laser of wort shooting 35' across your brewery, hitting the opposite wall, and splashing 25' in every direction. Only then is using a valve bad.

[Brewtime]

You're trying to solve a problem that doesn't exist in the first place.

1) HSA is a myth.

2) VFD's only work with 3-phase motors (I'm 99% certain)

3) a valve downstream of the pump is the ideal way to throttle flow on a March pump

The only time using a valve is bad is if you have your own brewery, you're stupid, the VFD for your 5hp brewhouse pump burns out and you're forced to throttle wort flow with valves, you accidentally route the wort to a section of the manifold that is necked down to 1" and is disassembled for maintenance, and you get a 100gal/min laser of wort shooting 35' across your brewery, hitting the opposite wall, and splashing 25' in every direction. Only then is using a valve bad.

First hand experience

[ValonaBrewingCo]

Actually, my EE co-worker and I were thinking about making a single phase VFD just as a fun electronics experiment. Trust me though, NOBODY makes them commercially because not many customers are interested in putting a $500 controller on a $100 motor. If you think that your pump might be having an affect on your final product, then just do without it. Better yet, split a batch of pumped and un-pumped and let us know if you detect a difference.

[buffalobrewer]

if you are real concerned about this a router speed controller might work. rockler.com sells them.

[OhioBrewingTech]

You need one of these:

http://www.coleparmer.com/techinfo/tech ... htm&ID=580

Actually, you don't. But these do what you ask.

[Roc-Craven]

You're trying to solve a problem that doesn't exist in the first place.

1) HSA is a myth.

2) VFD's only work with 3-phase motors (I'm 99% certain)

3) a valve downstream of the pump is the ideal way to throttle flow on a March pump

The only time using a valve is bad is if you have your own brewery, you're stupid, the VFD for your 5hp brewhouse pump burns out and you're forced to throttle wort flow with valves, you accidentally route the wort to a section of the manifold that is necked down to 1" and is disassembled for maintenance, and you get a 100gal/min laser of wort shooting 35' across your brewery, hitting the opposite wall, and splashing 25' in every direction. Only then is using a valve bad.

OH My! (said in Sulu's voice)

[marvelman74]

I use a Tuthill pump. It runs off a DC motor that is infinitely variable on the speed. The pump is all 316 stainless and has interlocking gear impellers (no priming needed) to run the wort. I can run it at a trickle for sparging or full bore for wort transfer. It is mounted on an old stainless sink. The DC power supply is inside the base. On the front left corner is the potentiometer that lets me control the motor speed. The only downfall, it is about 3 to 4 times the price of a March pump. I have a March pump too, and there is no comparison.
In my honest opinion, put a valve on the outlet of your pump, throttle it back, relax and have a homebrew. Like someone told me, you will mess something else up during the process of brewing so don't dwell on the little stuff that doesn't matter.