trainee in need to help

[schinkae]

hi im a trainee in need of help!
im revising for my 309 science and principles exam and i have some revison questions im going through,
the first one i could do with a hand with is:

"describe briefly how electronic devices may be used ina a motor speed conrol unit"


many thanks fro any responses

 

[Simonslimline]

They can be used to control the frequency which will control the speed. Ns = frequency x 60 divided by pairs of poles.

Have a read through the link below

http://www.ecollege.ie/site/liu/electrical_notes/LL241.pdf


I guess Mike is your tutor then in Bath College.

 

[schinkae]

Big si!! It's Sam I listened to you about getting on here although it might be too late haha

 

[Simonslimline]

Big si!! It's Sam I listened to you about getting on here although it might be too late haha

Whens the resit?

You should get access to the Trainee section on here. There is a list of mentors that will help with questions etc. Post up any others you have mate.

 

[schinkae]

Tuesday bro, I think I posted in it already not sure what's going on with it

 

[Simonslimline]

Cool well anymore questions just post em up.

The Trainee section is the one under this section. You will need to Ask for access by sending a PM to one of the Mods on here or leaving your details in the applying section.

 

[SirKit Breaker]

If you get really stuck with things, then eHow is always worth a look.

 

[Mathieu]

You can use thyristor stacks to control the speed of a motor, check Control Techniques web site for mentor drives .. They are commonly used at Tata steel works