In message <
RYGdnTpNP8ob-MnM...@bt.com>, MB
<M...@nospam.nospam> writes:
>On 27/03/2013 22:24, J. P. Gilliver (John) wrote:
>> In message <
5332849...@davenoise.co.uk>, "Dave Plowman (News)"
>> <
da...@davenoise.co.uk> writes:
>> []
>>> Didn't think the speedo was an MOT item in those days. Might have been
>>> different for commercial etc vehicles, though.
>>>
>> For cars, it still isn't. At least, its accuracy isn't; it may have to
>> work, FSVO work. (And I've heard it has to be in MPH not KPH.)
>
>
>
>From 2012
>
>Speedometer
>
>The car will fail if a speedometer is not fitted, is incomplete,
>inoperative, has a dial glass broken/missing or cannot be illuminated.
>
Inoperative, though - so as long as the needle moves? (Also, is the
odometer considered part of the speedometer?)
>
>
>Found this on speedometer accuracy on the Honest John website
>
>However on checking Reg 35 MV(Con and Use)Regs 1986 all that is stated
>is that speedometers have to be fitted to certain vehicle. No mention
>of accuracy.
>Reg 36 outlines that they have to be maintained but again no criteria
>on accuracy .
>
>To get Type Approval on Speedo the following test done
Type approval isn't the same as testing each one, though; it's
(approximately) checking the prototype. (Of the vehicle, not the speedo,
based on what follows.)
>4.3. The accuracy of the speedometer equipment shall be tested in
>accordance with the following procedure: 4.3.1. the vehicle is equipped
>with one of the types of tyre normally fitted ; the test shall be
>repeated for each of the types of speedometer specified by the
>manufacturer; 4.3.2. the load on the axle driving the speedometer
>equipment must correspond to the weight complying with 2.6 of Annex I
>to Directive No 70/156/EEC; 4.3.3. the reference temperature at the
>speedometer shall be 23 � 5� C; 4.3.4. during each test the pressure of
>the tyres shall be the normal running pressure as defined in 2.3;
>4.3.5. the vehicle is tested at the following three speeds : 40, 80 and
>120 km/h, or 80 % of the maximum speed specified by the manufacturer,
>if this is inferior to 150 km/h; 4.3.6. the test instrumentation used
>for measuring the true vehicle speed shall be accurate to � 1.0 %;
>4.3.6.1. the surface of a test track when used be flat and dry, and
>shall provide sufficient adhesion. 4.4. The speed indicated must never
>be less than the true speed. At the speeds specified for the test in
>4.3.5 above and between these speeds, there shall be the following
>relationship between the speed indicated on the dial of the speedometer
>EEC Reg 75/443/EEC.
>Again no error other than cannot show doing less that true speed.
I take it that "no error other than" that is from the EEC reg. you
quoted.
Sounds like these rules were drawn up by two different people (or
committees): one being very careful, about tyre pressures, load, and so
on, all of which sounds like the intention _was_ to specify accuracy;
the second just saying it mustn't under-read (presumably to reduce the
likelihood of a defence against a speeding ticket). I suspect the first
committee were rather cross with the second, after they'd put all that
effort in (-:!
So for type-approval of a vehicle model in the first place, the speedo
must not under-read; and from 2012, the speedo on each car tested must
not be "inoperative", though that suggests there is still no _accuracy_
requirement.
Back to Foyle's war: my immediate thought on seeing a bus in it, with
authentic-looking (to me) adverts on it, was "oh yes, this is ITV, who
can spend lots of money on authenticity, and want us to be aware that
they've done so"; interesting to read that they slipped up on the bus
itself (-:!
--
J. P. Gilliver. UMRA: 1960/<1985 MB++G()AL-IS-Ch++(p)Ar@T+H+Sh0!:`)DNAf