In article ,
Graham Murray wrote:

But as has already been pointed out, the speed limit can depend of the
class of vehicle. Speed cameras only enforce the speed limit for those
vehicles subject to the highest limit at that location. So if a vehicle
is travelling faster than the limit which applies to it but slower than
the limit which applies to the least restricted class of vehicle, the
camera will not detect that is exceeding its maximum permitted
speed.

I was talking to a truck driver a couple of months ago (he was driving
the truck taking my ailing car home on the back of it) and he was of the
opinion that at least some speed cameras can detect the size of a
vehicle and react to its speed accordingly. I'm still not sure whether
to believe it, but he slowed down to 40-ish for the cameras his satnav
told him about (A68 - not many).

Sam

In message
Chris Tolley (ukonline really) wrote:

Graeme wrote:

[snip]

One could argue the other way too, in that big vehicles have
tachographs, while small ones don't. I was once aboard a coach on
the A12 that was flagged down by a police officer who then boarded
it, looked at the recording, and issued a ticket accordingly.

Techographs can be tampered with and if you are totally reliant on
cameras to enforce speed limits there won't be any police officers around
to flag down errant HGVs/PSVs. Which is exactly what has been happening.
And white van man gets away with it both ways.

Any particular reason for making the same point after it has already been
acknowledged?

You were the one that introduced tachographs into the discussion. I was
merely answering that point.

Indeed. It took you five words. I was talking about the sixth and
subsequent.

Which were in reply to your anecdote, do you have a problem with that?


It sounds like you are trying to convince me that just because a system
can't do everything, it shouldn't do anything.

I fail to see how you arrive at that conclusion.

I can't see any other reason that you would repeat the point about HGVs
PSVs and Mr W Van. That's why I asked why you repeated yourself when the
points had already been acknowledged.

Because you don't appear to have understand my points.


Despite your earlier protestations you don't seem to be understanding
the point I have been making.

All you seem to have said is that speed cameras don't make roads safer
and they don't catch everyone who is speeding.

You don't appear to have understood my points at all. Indeed you seem to
prefer rewording what I have said to fit your own agenda so there seems
little point in continuing this discussion.

--
Graeme Wall

This address not read, substitute trains for rail
Transport Miscellany at www.greywall.demon.co.uk/rail
Photo galleries at http://graeme-wall.fotopic.net/

Graeme wrote:

In message
Chris Tolley (ukonline really) wrote:

Graeme wrote:

[snip]

One could argue the other way too, in that big vehicles have
tachographs, while small ones don't. I was once aboard a coach on
the A12 that was flagged down by a police officer who then boarded
it, looked at the recording, and issued a ticket accordingly.

Techographs can be tampered with and if you are totally reliant on
cameras to enforce speed limits there won't be any police officers around
to flag down errant HGVs/PSVs. Which is exactly what has been happening.
And white van man gets away with it both ways.

Any particular reason for making the same point after it has already been
acknowledged?

You were the one that introduced tachographs into the discussion. I was
merely answering that point.

Indeed. It took you five words. I was talking about the sixth and
subsequent.

Which were in reply to your anecdote, do you have a problem with that?

I am sure Marcus Porcius Cato would have given a similar answer. ;-)

Despite your earlier protestations you don't seem to be understanding
the point I have been making.

All you seem to have said is that speed cameras don't make roads safer
and they don't catch everyone who is speeding.

You don't appear to have understood my points at all. Indeed you seem to
prefer rewording what I have said to fit your own agenda so there seems
little point in continuing this discussion.

I have no agenda on this issue, other than a desire to see people
present logical and verifiable arguments.

I apologise for my reckless disregard for the content of your points
evidenced by my summarising them with words you would not have chosen.
I intended no disrespect.

--
http://gallery120232.fotopic.net/p11938601.html
(45 132 at Alresford (Hampshire), 2 Sep 1999)

In message
Chris Tolley (ukonline really) wrote:

Graeme wrote:

In message
Chris Tolley (ukonline really) wrote:

Graeme wrote:

[snip]

One could argue the other way too, in that big vehicles have
tachographs, while small ones don't. I was once aboard a coach on
the A12 that was flagged down by a police officer who then boarded
it, looked at the recording, and issued a ticket accordingly.

Techographs can be tampered with and if you are totally reliant on
cameras to enforce speed limits there won't be any police officers around
to flag down errant HGVs/PSVs. Which is exactly what has been happening.
And white van man gets away with it both ways.

Any particular reason for making the same point after it has already been
acknowledged?

You were the one that introduced tachographs into the discussion. I was
merely answering that point.

Indeed. It took you five words. I was talking about the sixth and
subsequent.

Which were in reply to your anecdote, do you have a problem with that?

I am sure Marcus Porcius Cato would have given a similar answer. ;-)


But, alas, Kato would not have been so obliging.

cue Pink Panther Theme

Coincidentally I've just been studying Hannibal's campaign in Italy.

--
Graeme Wall

This address not read, substitute trains for rail
Transport Miscellany at www.greywall.demon.co.uk/rail
Photo galleries at http://graeme-wall.fotopic.net/

On Wed, 28 Jul 2010 10:32:48 +0100, Chris Tolley
(ukonline really) wrote:

Adrian wrote:

Considering HGVs are physically restricted to below the legal speed
limit

Some might be. Clearly not all are. I have been overtaken on the M6 by
an HGV while doing 70mph (as measured by GPS, not speedo).

They are not restricted with an auto brake - that would be dangerous
in slippy conditions, for instance. So if going downhill, they might
well reach 70mph or more.

The limiter just cuts engine power when the appropriate speed is
reached.

Neil
--
Neil Williams in Milton Keynes, UK
To reply put my first name before the at.

Sam Wilson gurgled happily, sounding much like they
were saying:

But as has already been pointed out, the speed limit can depend of the
class of vehicle. Speed cameras only enforce the speed limit for those
vehicles subject to the highest limit at that location. So if a vehicle
is travelling faster than the limit which applies to it but slower than
the limit which applies to the least restricted class of vehicle, the
camera will not detect that is exceeding its maximum permitted speed.

I was talking to a truck driver a couple of months ago (he was driving
the truck taking my ailing car home on the back of it) and he was of the
opinion that at least some speed cameras can detect the size of a
vehicle and react to its speed accordingly. I'm still not sure whether
to believe it, but he slowed down to 40-ish for the cameras his satnav
told him about (A68 - not many).

The theory is commonplace, but I doubt the practice - not least because
it's entirely possible for two nominally visually identical vehicles (and
certainly very similar in overall outline or cross-section) to have
different speed limits.

Basically, I just don't think the cameras are intelligent enough.

Talivans, otoh...

On Jul 28, 9:53*pm, Adrian wrote:
Sam Wilson gurgled happily, sounding much like they
were saying:

But as has already been pointed out, the speed limit can depend of the
class of vehicle. Speed cameras only enforce the speed limit for those
vehicles subject to the highest limit at that location. So if a vehicle
is travelling faster than the limit which applies to it but slower than
the limit which applies to the least restricted class of vehicle, the
camera will not detect that is exceeding its maximum permitted speed.
I was talking to a truck driver a couple of months ago (he was driving
the truck taking my ailing car home on the back of it) and he was of the
opinion that at least some speed cameras can detect the size of a
vehicle and react to its speed accordingly. *I'm still not sure whether
to believe it, but he slowed down to 40-ish for the cameras his satnav
told him about (A68 - not many).

The theory is commonplace, but I doubt the practice - not least because
it's entirely possible for two nominally visually identical vehicles (and
certainly very similar in overall outline or cross-section) to have
different speed limits.

Basically, I just don't think the cameras are intelligent enough.


Well, the cameras don't need to be that intelligent. The software for
working out the fines can do a final check on whether the speed is
legal for the vehicle in question.

Andy gurgled happily, sounding much like they were
saying:

The theory is commonplace, but I doubt the practice - not least because
it's entirely possible for two nominally visually identical vehicles
(and certainly very similar in overall outline or cross-section) to
have different speed limits.

Basically, I just don't think the cameras are intelligent enough.

Well, the cameras don't need to be that intelligent. The software for
working out the fines can do a final check on whether the speed is legal
for the vehicle in question.

So you're suggesting that the cameras in a 60 limit single carriageway NSL
should take a photo of every vehicle doing over 40mph, in case they might
be HGVs?

Given that most cameras are still analogue, I think they might just as
well leave the film-changing-chappy on site, because he's got a busy time
ahead of him.

On Jul 28, 10:05*pm, Adrian wrote:
Andy gurgled happily, sounding much like they were
saying:

The theory is commonplace, but I doubt the practice - not least because
it's entirely possible for two nominally visually identical vehicles
(and certainly very similar in overall outline or cross-section) to
have different speed limits.

Basically, I just don't think the cameras are intelligent enough.
Well, the cameras don't need to be that intelligent. The software for
working out the fines can do a final check on whether the speed is legal
for the vehicle in question.

So you're suggesting that the cameras in a 60 limit single carriageway NSL
should take a photo of every vehicle doing over 40mph, in case they might
be HGVs?

No, just that if, as suggested, they have the capability to check for
'large' vehicles which have a lower speed limit, there can be a final
check of the speed before fines are issued.


Given that most cameras are still analogue, I think they might just as
well leave the film-changing-chappy on site, because he's got a busy time
ahead of him.

And the newer installations are digital, which would remove most of
the problems.

Andy gurgled happily, sounding much like they were
saying:

Basically, I just don't think the cameras are intelligent enough.

Well, the cameras don't need to be that intelligent. The software for
working out the fines can do a final check on whether the speed is
legal for the vehicle in question.

So you're suggesting that the cameras in a 60 limit single carriageway
NSL should take a photo of every vehicle doing over 40mph, in case they
might be HGVs?

No, just that if, as suggested, they have the capability to check for
'large' vehicles which have a lower speed limit, there can be a final
check of the speed before fines are issued.

Ah, I'm with you. Take a photo of anything believed to be large, and
double-check before fining. Hmm. Still don't think they're intelligent
enough to do that.

Given that most cameras are still analogue, I think they might just as
well leave the film-changing-chappy on site, because he's got a busy
time ahead of him.

And the newer installations are digital, which would remove most of the
problems.

Newer ones are, yes. But they're still very much the minority.