Slip Rings vs. Slip Ring Commutators (1 Viewer)

[wagig]

Hi everyone,
I've come across a problem concerning the difference between "Slip Rings" and "Slip Ring Commutators" (and NO i don't mean Split Ring Commutators). By my understanding, the correct term should be "Slip Rings" (without the word "Commutator"), as the idea of a commutator is to maintain a direct current- something that Slip Rings do NOT do.

In my exam on motors and generators there was a question which displayed a picture of a generator (not given whether it is AC or DC) not showing the connection to the external circuit, i.e. the brush + split ring commutator for DC, or the brush + slip rings for AC. The question asked, "The diagram above has an important part of any motor missing, what is it, and why is it important" and my teacher's answer was "Commutator. Slip Ring Commutator maintains connection between rotor and stator of motor, Split Ring Commutator reverses the current direction every half turn, ensuring current flows in single direction.".

So my questions are these:
1. Is the term "Slip Rings" or "Slip Ring Commutators"?
2. In a HSC exam, would my teacher's answer be rewarded 3/3 marks?
3. Would HSC markers even care whether we use "Slip Rings" or "Slip Ring Commutators"?

I guess it's kind of arguing semantics, but i'd like to minimise any possible loss of marks in my HSC exam
Thanks in advance haha

 

[QZP]

Yes, it's more correct to say "slip rings" rather than "slip ring commutators" simply because a commutator is a device that switches current direction.
You'd still get full marks for saying the latter.

 

[anomalousdecay]

Yes, it's more correct to say "slip rings" rather than "slip ring commutators" simply because a commutator is a device that maintains current direction.

No.

Remember that for DC, the commutator changes the direction of the current to maintain the rotation of the motor in the same direction.

Slip rings work instead of using a brush. By no means are they a commutative device. The commutative device in an AC motor is actually the power source (this is out of syllabus scope).

You'd still get full marks for saying the latter.

In HSC you would as you don't get penalised for saying wrong stuff. But be wary that the marker could think that you are under misconception and not deserving of a Band 6 mark. It is just simply wrong to say slip rings are commutators. There is no such thing.

 

[QZP]

Yep sorry wrong word. maintain --> switch lol

 

[anomalousdecay]

Yep sorry wrong word. maintain --> switch lol

Haha no problem.

The HSC syllabus doesn't really go into depth as it should on commutative devices.

We are just left with the one meaning for commutators when there are many different types of commutators.