Frequencie converter

distillate

#1

So i hooked My. Vacuum pump up. To a frequencie converter
This makes iT possible to manipulate the cfm of the pump
Doesn t. Effect vacuum depht If You have No leaks!
Since pumps are getting large and @BreakingDabs told aboat muffins in boiling flaskk due to to large cfm
I. Am giving iT a shot there seems Some vacuum löss at -20 % down turning of the rpm of the motor but minimal
Any body ever fiddled with this ?


#2

not on a vacuum pump.
got one on my centrifuge(s)

and it’s a similar trick to the PWM that makes my electrick car so much fun :wink:


#3

I use a variac on those :grinning: Works Ok gets the panda down to 2400 rpm


#4

Seems like a decent method. Would a variac accomplish the same thing?


#5

Variac and motors aren t the best match
Get a variac at 2x the motor W and iT works
Frequincy converter do work better
Never notice on a panda spindryier iT says 3200 rpm at60 hz 2800rpm at 50 htz


#6

Netherlands have 50htz :confounded:


#7

My fear would be to lower frequency to a point where the motor won’t run


#8

Altering the frequency rather than the voltage allows for speed control on many AC motors, which are generally driven as a multiple of line frequency by the nature of their design. changing “line” frequency changes how fast they go.

Pulse Width Modulation can be used on AC or DC motors, and is basically just switching the power on an off. fast. the older EV’s like mine used an audible frequency to switch at. the new ones don’t. it doesn’t give speed control so much as “power” control. however, it equates to a similar thing if the motor is under load.


#9

O the converter i have can only lower or rise 20% and she still spins then


#10

Would a frequency converter ( we aren’t talking vfd here right) still keep the full torque of the AC motor?


#11

yep. you can do that. 0 Hz :wink:

We are currently running the pump motor on our Autovap at around 4.5Hz until we get the bigger water heater installed.

we start our ethanol circulation pumps at 30Hz and usually don’t take them past 40Hz. The ability to run them backwards is helpful. But that is a trick reserved for 3-phase motors I believe.

on the Ace15, we can get agitate, then spin. and store the profiles.


#12

Treuth i don t really know as i understand Yes but the motor also uses less power


#13

Full Torque?
That’s my understanding.
Available amps and volts don’t change.
just how quickly one is encouraged to spin in circles :wink:

of course, asking once a second vs 50 or 60 times would seem to provide less motivation (Power).


#14

What is your normal electric frequincie ?


#15

the walls in OR have the 60 cycle hum.


#16

I think i found 5 Ways to write frequency and not. One makes sense​:rofl::rofl::rofl:


#17

Damit your panda’s do go 3200😀


#18

Could we get the panda’s to 4000 rpm :stuck_out_tongue_winking_eye:


#19

probably. it certainly looks like the larger clothes dryers can handle being over driven.


#20

Yea… i use valves to mitigate cfm draw issues these days. But having a vfd on some of the bigger pumps would be coold.