OT : generating 240v AC...?

Indeed. There are some amazing tricks with it on YouTube.

I have too much time on my hands, probably.

Regards,

Simonm.

There was a hands on science exhibit at a museum we visited in Phoenix last year, where you wore rubber gloves in a tank of the stuff - its like switchable slime. Yuk.

Steve

determined

generator

Tell him to google on converting 3 phase motors to alternators. It is much done in the 3rd world. In essence all that is needed is to connect three capacitors in a triangle, with the points of the triangle connected to the three phase connections of the motor. Capacitors need to be ac rated so NOT electrolytics, and their size is dependant on the motor characteristics. Three phase biggish motors can be had for scrap price.

AWEM

This is how asynchronous generators work, the rpm still sets the frequency as they need to be drive about rated speed but the capacitors control the voltage. I'm told these capacitively excited sets don't like inductive loads as they destroy the excitation.

Presumably your big genset is a conventional one with rotor field fed by slip rings?

But what is he going to use to turn it? That little water wheel won't at least not if there is any load on the "generator"... And where is the excitation current going to come from or is such a conversion self-exciting (Oh er missus!)?

Dave Liquorice wrote: ... And where is the

(Point taken about speed). AFAIK, many 3phase motor alternator jobbies will self excite with any residual field in the armature.

How many bloody engineers ARE there in this NG ?

Steve

Stands to reason - the capacitors shift the phasing one way, the inductors exactly the opposite....

Steve

Don't ask me for pictures, they're REALLY scary.

Steve

In which case adding capacitance would offset this but what happens to the voltage?

AJH (treechopper)

How many do you want?

Enough to get the job done, few enough to keep the salaries high enough to live on :)

Lizzy

Network Rail are working on it. Haven't quite got the balance right yet.

Do you mean engineers or railway maintenance workers ?

Steve

I am a RF (Radio) engineer.. does that make it 3?

Make that 4. (Automotive Engineer)

On or around Thu, 31 Jan 2008 17:54:13 +1300, EMB enlightened us thusly:

I put "engineer" sometimes on those forms that want "occupation."

Depends how it's spelt!

So do I, most computer systems that want an occupation don't list mine or anything close. I'm a freelance Broadcast Sound Engineer. I studiously avoid anything mention of "media" or "entertainment" particulary with insurance companies.