P plate training ...not

errm in line with the definition of a poofteenth, you've unfortunately
been sucked in by a common misconception

http://en.wikipedia.org/wiki/Deux_Chevaux

The 2CV had 2 *TAX HP* - the bottom of the range 375cc twin produced
about 9HP (ie BHP/DIN).

Both England and France had tax HP ratings around this period - they
were basically statutory calculations and led to some odd engine
designs to minimise tax in England (long stroke small bore were
cheaper than short stroke motors of the same capacity)

http://en.wikipedia.org/wiki/Tax_horsepower

JL

 

I wonder... I'm sure you know more about how well it's calibrated then
me, but I suspect it's probably got enough resolution to see 1% changes
in the flow rate even if the numbers it displays aren't all that
relevant - I _think_ the fuel injection system would be representing a
real world flow rate increase of 1% when the display changes from 10.0
to 10.1 at a constant speed, even it it's not actually flowing 10L/hour
(or whatever) at the time...

big

 

Fair enough, so maybe it's only 3 and a bit percent - my point still
stands (and if it was anyone other than disingenous-hammo arguing wiooth
me I'd consider apologising...)

;-)

big

 

The way I understand it that statement is wrong , mechanical input
required to generate electrical energy bears relationships to each
other, more electrical energy required means more drive is required to
overcome the resistance to turning .A change in turning momentum is
proportional to energy required.

 

Point ! Point well made.

JL

 

And your statement is indeed correct - there's a difference between
the mechanical input and the mechanical load. Pure semantics of
course. mechanical load (as torque) plus electrical load(as torque)
equals mechanical input required(as torque). The mechanical load is a
constant (ceteris paribus), the electrical load changes with, well,
the electrical load <grin> (1). To be more accurate the torque/turning
force that you have to provide to generate a current equal to the
current being drawn is increased as the current required increases(2)


JL
(1) there obviously being more than one meaning of the word load in
this context - one being current drawn, the other being turning force
required
(2) still not sure I'm explaining that particularly well

 

I think he's saying that if you turn an alternator with no load and with
full load, no extra power input is required. That must be why our back-up
gen-set gets louder when we put the air-con load on it. 3.9 litre John Deere
with a 3 phase 44kw alternator.

Anybody want to tell me it doesn't use more fuel when we load it up to 40
kw?

Try holding one of these permanent magnet alternators in your hand and spin
the rotor with your other hand. Easy isn't it? Now twist the output wires
together and give it another spin. That would be max load. What do you mean
it stops dead? It surely doesn't require more turning force?

Simple brakes for an induction motor is to short the terminals together.
This is wired into a lot of machinery. Stops very quickly. An induction
motor is the same design as your perm magnet alternator.

Theo

 

What kind of a bus is that?

Those of us that agreed with you understood it.

Theo

 

Isn't petrol just very old solar power?

Theo

 

Well, as they do work as switch mode power supplies, it is not a total loss
system and when you turn on the headlights you will use more, albeit only a
tiny bit more, power from the engine, requiring more fuel.

Theo

 

True, as a general rule the red ones are faster and this has been a concern
to (most) motorcycle manufacturers worldwide.

Having a fast red light at the rear of the motorcycle was a huge concern in
the early days of motorcycling as it was soon realised that having a fast
light (red) at the rear and a not-so-fast light at the front led to the rear
of the motorcycle trying to overtake the front at every opportuity - this
was deemed to be "not rider friendly".

To counteract the power of the red light, a very mild or low wattage light
was fitted to the rear whilst a stronger/higher wattage light was fitted to
the front. This has worked very well.

The ratio between front and rear light is very sensitive. A typical setup of
60/55 watt high/low beam front light to 5 watt tail light works well in most
situations but the addition of a 20 watt brake light has added an element of
danger by making the motorcycle unstable. If you require proof of tis, try
the following:

- ride along (at any speed) with the mind in neutral and then apply the
front brake as hard as you possibly can and do not ease off under any
circumstances. The rear of the motorcycle will rise and continue rising
until the red, rear light has overtaken the front. Some will try and
attribute this phenomenon to the action of the brakes but that is not 100%
correct. Squeezing the front brake as hard as you can imparts maximum energy
to the faster red light. A similar effect can be achieved by applying
maximum force to the rear brake.

So yes the red lights are the fastest but they can be tamed with some
(un)sound engineering practices so as not to detract from the motorcycling
experience.

 

I wasn't going to shove my oar in again but that's such a good
translation I can't resist it. Of course you have to spin the
electricity generating thing faster if you want more electricity,
nobody's arguing that you don't. What I was saying was that the
increased electrical load does not cause engine RPM to drop, because it
can't.

Simple test: drive a test vehicle (use Nev's) to a stadium with lights
and connect lights to a light circuit on the test vehicle (don't ask me
how, there seem to be a gadmillion electrical geniuses in here, you lot
figure it out). Step 2: turn on lights. If I'm wrong the test vehicle
will stall. If I'm right the lights won't come on but the test vehicle
will run normally.

 

I will never agree to that ( I stick to what I know and have been taught)

- one being current drawn, the other being turning force

load is load , as in work to be done /required so whether explained as
turning force or current drawn they bear a direct relationship of watts
and where's consumed

No you didn't , I suspect it's some bullshite machination dreamed up
to split hairs buy a drunken masturbaterpoofta ( tell me if I am wrong)

sounds a little like the wider tyre wont stick as well crap /

 

No need. Our generators at work drop revs and sound as if they're under
load instantly when we turn on spotlights connected to them. There's no
doubt they'd be using more fuel.

Of course, whether that's a "waste" of petrol depends on your point of view.

I'm Toosmoky and that's my two bob's worth.

 

In fact if you take an ungoverned motor driving a genny it will in that
circumstance slow in revs due to load increase which is why a governing
unit is used to maintain speed , now do you agree ?

 

One of the less talked-about "passions"........

 

Now that you mention it; I think I read that the Qld electric and
diesel-electric trains use this system for brakes.
The added advantage is that without turning there's no back-EMF so they're
essentially anti-lock.

 

My figures were measured at the bowser, rather than relying on the trip
computer, which invariably shows worse fuel consumption than reality.
The odometer and speedo in the car are near enough to accurate, plus or
minus 1kph or 1% or so.

Nev..
'04 CBR1100XX

 

My old mach111 certainly used to conform to this principle!

 

Quantify "measured".