Dynamometers

"Maynard A. Philbrook Jr." fired this volley in news: snipped-for-privacy@news.eternal-september.org:

"Electro-Majic DC". It couples directly to AC lines with no problems. No need for syncronous inverters, no voltage control, no nothin'. Just hook it up and pedal your bike for an instant reduction - and even payback - on your power bill!

Lloyd

I think you're going to be disappointed with your understanding of it.

Jamie

Well I am glad you straighten me out on that!

Jamie

"Maynard A. Philbrook Jr." fired this volley in news: snipped-for-privacy@news.eternal-september.org:

No, I think he's perfectly comfortable with his understanding of it. It would be entertaining to watch when "understanding" meets "mains".

Lloyd

Had a bunch of them at a previous job (225D and 240D) do not profess that I understand how they worked, but do why they were needed in our application. Large slowly spinning arms with molds attached which were never truly balanced. Regenerative drives help get back *some* of the energy used to raise the heavy side as it falls and the light side rises.

Also astounded by the difference in appearance between 20 + year old drive boards and there modern replacements. Old ones are absolutely crammed with components, new one look almost bare! Will try to get a picture the next time I'm down that way...

Oh, posting from rec.crafts.metalworking. Just noticed this is cross posted to two groups I am not following.

I can't believe it..

Ring the dinner bell and they all come out of the wood work!

Jamie

The only ones I've seen have been for battery operation - wouldn't be the first thing I missed.

That control does NOT put power back into the grid. It is a "plugging" brake that reverses the torque on the motor to stop it. Standard 4 quadrant control. They call it "regenerative" braking, but in reality it is "dynamic" braking.

Explain the difference, please.

Do your own research.

So, you do not understand the meaning of 4-quadrant operation, it seems.

Here is the difference in dynamic and regenerative braking:

Obviously.

Like you, for example.

finally! we have a winner!

Jamie

Ur dense... it's obvious..

Jamie

I don't need to, I already know how it works.

Jamie

That's your normal response when you have egg on your face.

Jamie

True regenerative braking puts power back into the supply. Dynamic braking uses electromagnetic force to brake, but does not return the power to the source. DC dynamic braking can also be regenerative. AC dynamic braking is seldom regenerative. This particular unit is not. It is described as an AC 4 quadrant controller for a DC motor - and that is what it is..