Flashing lights

On Wed, 02 Nov 2005 23:18:47 GMT, [email hidden] (Jim Ley) said in
<[email hidden]>:

Quoted message said:

Surely the LED's even in steady mode are actually flashing, just at a
rate your eyes can't detect...

More than 4 per second? Illegal, that is, mate...

Guy
--
http://www.chapmancentral.co.uk

"To every complex problem there is a solution which is
simple, neat and wrong" - HL Mencken

Expect to see police

Quoted message said:

Quoted message said:

Quoted message said:

horses with flashing blue lights.

Police bicycles already have them.

There's quite a few kids around at the moment with those flashing blue dust
caps given as freebies t'other month on a mag.

I didn't think that was legal!!

AW

In message <[email hidden]>, Danny
Colyer <[email hidden]> writes

Quoted message said:

Just zis Guy said:

Gaaaaah! Amendments to SIs make my head hurt. Where's Tony Raven?
OK, specifically: it looks as if the kitemarking requirement is
relaxed but *only* in respect of lamps not capable of emitting a
steady light (i.e.: almost none of them), but that the fact of a lamp
being able to emit a flashing light makes it legal whether used steady
or not. Or am I misreading it? It has been a long day....

That's how I interpreted it to start with, although I've since realised
(on about the fourth reading) that the lamp *must* be used in flashing
mode in order to get round the kitemarking (or equivalent) requirement.

Hmm not sure I agree with that, if it has steady mode and then it still
needs an approval mark in my reading, even if you are just using the
flashing mode. The flashing mode may meet the requirements (4 candela)
but the lamp would still not be legal without the approval mark.

Quoted message said:

I e-mailed the CTC last week requesting clarification. As you'd expect,
I had a helpful reply from Chris Juden:

CJ > Not so. The cycling press and message boards are full of
CJ > ill-informed comments on cycle lighting. See here:
CJ > http://www.ctc.org.uk/DesktopDefault.aspx?TabID=4071 for the truth.

Seemed like good summary.

Quoted message said:

DC > Also, how do you think the law would handle a Cat Eye TL-LD600 in
DC > strobing (Cylon effect) mode? I dislike simple flashing lights and
DC > refuse to use one, but I like the effect of a moving light (as long
DC > as it is used alongside at least one steady light) and usually use
DC > one when riding after dark. I fear it may fall foul of the maximum
DC > flashing rate (240 flashes per minute), which I otherwise
DC > thoroughly approve of. By my measurements the lamp emits about 600
DC > flashes per minute. Each individual LED would flash only about 150
DC > times per minute, but the strobing pattern means that the intervals
DC > between each display of light for an individual LED are not
DC > constant.

Quoted message said:

CJ > I am not familiar with that lamp. The upper limit on flash
CJ > frequency is to avoid triggering epileptic fits, which is a
CJ > particular risk with lights that flash at a rate between 5 and
CJ > 30Hz. I am not an expert on epilepsy but suppose that when an LED
CJ > array is used to produce the effect of a moving light, that
CJ > perception takes sensory precedence over what any individual LED
CJ > may be doing.
CJ >

There is also a requirement that flashing lights have steady flash -
the amendment to part 1 schedule 10 says:

'the intervals between each display of light shall be constant'

I can't decide whether the LD600 etc with strobe patterns would fit in
with this.

--
Chris French

chris French said:

In message <[email hidden]>, Danny
Colyer <[email hidden]> writes

Quoted message said:

DC > Also, how do you think the law would handle a Cat Eye TL-LD600 in
DC > strobing (Cylon effect) mode? I dislike simple flashing lights and
DC > refuse to use one, but I like the effect of a moving light (as long
DC > as it is used alongside at least one steady light) and usually use
DC > one when riding after dark. I fear it may fall foul of the maximum
DC > flashing rate (240 flashes per minute), which I otherwise
DC > thoroughly approve of. By my measurements the lamp emits about 600
DC > flashes per minute. Each individual LED would flash only about 150
DC > times per minute, but the strobing pattern means that the intervals
DC > between each display of light for an individual LED are not
DC > constant.

Quoted message said:

CJ > I am not familiar with that lamp. The upper limit on flash
CJ > frequency is to avoid triggering epileptic fits, which is a
CJ > particular risk with lights that flash at a rate between 5 and
CJ > 30Hz. I am not an expert on epilepsy but suppose that when an LED
CJ > array is used to produce the effect of a moving light, that
CJ > perception takes sensory precedence over what any individual LED
CJ > may be doing.
CJ >

There is also a requirement that flashing lights have steady flash -
the amendment to part 1 schedule 10 says:

'the intervals between each display of light shall be constant'

I can't decide whether the LD600 etc with strobe patterns would fit in
with this.

imo it all comes down to whether it is regarded as one light or five.
Each LED flashes within the allowed range and the interval between
flashes is constant (even though the duty cycle isn't even). The unit,
as a whole, emits flashes as too high a rate although the intervals are
still constant. You might argue that if there is no gap between one
LED going out and the next one lighting then it is a constant light
source although you might risk falling foul of teh restrictions on
moving lights

best wishes
james

I said:

Quoted message said:

ISTR a discussion here a while back about whether luggage attached to
the bike counts as part of the vehicle, but I don't think we came up
with a definite answer. If it /does/ count as part of the vehicle then
I guess the white reflective patches on my Ortlieb panniers would
probably be illegal as well.

and David Martin responded:

Quoted message said:

Well, as your pedals are probably illegal anyway, and would be obscured
by the luggage, it seems to be a moot point.

Well, yes, my pedals are illegal (the reflectors can't be seen from the
front or rear, only from above or below). I like to stay within the law
as far as possible, though, and to know exactly where I'm outside it.

--
Danny Colyer (my reply address is valid but checked infrequently)
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chris French said:

There is also a requirement that flashing lights have steady flash -
the amendment to part 1 schedule 10 says:

'the intervals between each display of light shall be constant'

I know said:

Quoted message said:

Each individual LED would flash only about 150
times per minute, but the strobing pattern means that the intervals
between each display of light for an individual LED are not
constant.

Quoted message said:

I can't decide whether the LD600 etc with strobe patterns would fit in
with this.

I don't think it would - see my reply to James.

--
Danny Colyer (my reply address is valid but checked infrequently)
<URL:http://www.colyer.plus.com/danny/>
Subscribe to PlusNet <URL:http://www.colyer.plus.com/referral/>
"He who dares not offend cannot be honest." - Thomas Paine

Chris French said:

Quoted message said:

'the intervals between each display of light shall be constant'

I can't decide whether the LD600 etc with strobe patterns would fit in
with this.

and James responded:

Quoted message said:

imo it all comes down to whether it is regarded as one light or five.
Each LED flashes within the allowed range and the interval between
flashes is constant (even though the duty cycle isn't even).

For an individual LED, the interval between flashes isn't necessarily
constant. If you imagine the LED's being numbered 1-5, the strobe
sequence is: 1,2,3,4,5,4,3,2,repeat. For LED's 1, 3 and 5, the interval
between flashes is constant. For 2 and 4, it isn't. For 2 or 4,
there's a flash, followed by 1 beat, then a flash, then 5 beats, then a
flash, then 1 beat again...

Quoted message said:

The unit,
as a whole, emits flashes as too high a rate although the intervals are
still constant.

Yup, about 2.5x too high a rate.

--
Danny Colyer (my reply address is valid but checked infrequently)
<URL:http://www.colyer.plus.com/danny/>
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"He who dares not offend cannot be honest." - Thomas Paine

Cliff Top said:

Expect to see police

Quoted message said:

Quoted message said:

> horses with flashing blue lights.

Police bicycles already have them.

There's quite a few kids around at the moment with those
flashing blue dust caps given as freebies t'other month on a
mag.

A motorcyclist passed me the other day with one on his rear wheel.
--
the.Mark

On 2 Nov 2005 14:50:42 -0800 someone who may be "David Martin"
<[email hidden]> wrote this:-

Quoted message said:

this does not seem to move us forward a

Quoted message said:

whole lot...

It does in that lights meeting EU standards equivalent to BS6102/3
2003(?) can be used.

They already could be used entirely legally. The Single European Act
would be the relevant legislation I assume.

--
David Hansen, Edinburgh | PGP email preferred-key number F566DA0E
I will always explain revoked keys, unless the UK government
prevents me by using the RIP Act 2000.

On Wed, 02 Nov 2005 23:36:50 +0000 someone who may be "Just zis Guy,
you know?" <[email hidden]> wrote this:-

Quoted message said:

Quoted message said:

Surely the LED's even in steady mode are actually flashing, just at a
rate your eyes can't detect...

More than 4 per second? Illegal, that is, mate...

Lamps powered by a "dynamo" also flash more than four times per
second.

Some claim that if they are filament lamps then they never actually
go out, due to time effects. However, the intensity varies more than
four times a second. I doubt if there is a definition of flashing in
any of these "laws" that states the lamp must go out entirely to be
flashing.

--
David Hansen, Edinburgh | PGP email preferred-key number F566DA0E
I will always explain revoked keys, unless the UK government
prevents me by using the RIP Act 2000.

David Hansen said:

Some claim that if they are filament lamps then they never actually go
out, due to time effects. However, the intensity varies more than four
times a second. I doubt if there is a definition of flashing in any of
these "laws" that states the lamp must go out entirely to be flashing.

Just like the pedal reflector regulation which states that the reflectors
must be placed on the "leading and trailing edges" of the pedals, but
fails to define them. I contend that on a recumbent there are leading and
trailing faces but not edges, in any practical sense of the term.

Mike

Danny Colyer said:

Chris French said:

Quoted message said:

'the intervals between each display of light shall be constant'

I can't decide whether the LD600 etc with strobe patterns would fit in
with this.

and James responded:

Quoted message said:

imo it all comes down to whether it is regarded as one light or five.
Each LED flashes within the allowed range and the interval between
flashes is constant (even though the duty cycle isn't even).

For an individual LED, the interval between flashes isn't necessarily
constant. If you imagine the LED's being numbered 1-5, the strobe
sequence is: 1,2,3,4,5,4,3,2,repeat. For LED's 1, 3 and 5, the interval
between flashes is constant. For 2 and 4, it isn't. For 2 or 4,
there's a flash, followed by 1 beat, then a flash, then 5 beats, then a
flash, then 1 beat again...

oops, yes, I was thinking 12345,12345. Maybe the "random" flash
function would be ok. CJs point about whether it is a moving constant
light source (versus several staionary flashers) was interesting
(though possibly not /much/ use until tested in court). I certaily
findthe "chasing mode" much more pleasant to follow on another cyclist
at close-ish range. All or "randon" flashing is rather distracting and
all on is just too bright.

Perhaps this is all a bit "angels on the head of a pin" though? Is
anyone actually aware of any attempts to reduce liability on the basis
of non-compliant (as opposed to absent) lighting on a cycle (in the
same way as has been attemtped WRT helmut wearing)?

best wishes
james

Mike Causer said:

Just like the pedal reflector regulation which states that the reflectors
must be placed on the "leading and trailing edges" of the pedals, but
fails to define them. I contend that on a recumbent there are leading and
trailing faces but not edges, in any practical sense of the term.

That regulation is requirement 2a of the table at
<URL:http://www.opsi.gov.uk/si/si1989/Uksi_19891796_en_25.htm#nsch20>

Now have a look at requirement 3:
"Angles of visibility: Such that the reflector on the leading edge of
each pedal is plainly visible to the front and the reflector on the
trailing edge of each pedal is plainly visible to the rear."

That's the one that's a problem on a recumbent.

--
Danny Colyer (my reply address is valid but checked infrequently)
<URL:http://www.colyer.plus.com/danny/>
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