Power Supply Units to GATSO cameras - update
Discussion
Following an allegation of 57mph on a 50mph dual carriageway, I have challenged my local constabulary on the basis of a complete lack of any maintenance schedule for the power supply unit within the GATSO cabinet.
Remember, that it is the camera module, that is moved from cabinet to cabinet, that is calibrated (in the Netherlands). Despite the fact that any other standards body would fall about laughing at the suggestion that a calibrated unit could be shipped across the North Sea, and then moved from site to site, and remain 'calibrated', you can't question GATSO calibration due to an earlier court ruling.
However, GATSO power supply units are not calibrated by my local constabulary - EVER (in over 10 years). The expert witness, who also works for the National Physical Laboratory setting standards for electronic measuring equipment, is under no doubt that it doesn't matter how well calibrated the camera module is, its accuracy cannot be guaranteed if the power supply hasn't been regularly checked.
Better still, it appears that the Constabulary is in breach of Health & Safety legislation (Electrical Equipment at Work). With officers routinely connecting camera modules into untested cabinets, it's only a matter of time before someone is electrocuted... the Police federation hasn't yet made a comment.
Any coppers out there know if their force's cabinet power supplies are tested?
Remember, that it is the camera module, that is moved from cabinet to cabinet, that is calibrated (in the Netherlands). Despite the fact that any other standards body would fall about laughing at the suggestion that a calibrated unit could be shipped across the North Sea, and then moved from site to site, and remain 'calibrated', you can't question GATSO calibration due to an earlier court ruling.
However, GATSO power supply units are not calibrated by my local constabulary - EVER (in over 10 years). The expert witness, who also works for the National Physical Laboratory setting standards for electronic measuring equipment, is under no doubt that it doesn't matter how well calibrated the camera module is, its accuracy cannot be guaranteed if the power supply hasn't been regularly checked.
Better still, it appears that the Constabulary is in breach of Health & Safety legislation (Electrical Equipment at Work). With officers routinely connecting camera modules into untested cabinets, it's only a matter of time before someone is electrocuted... the Police federation hasn't yet made a comment.
Any coppers out there know if their force's cabinet power supplies are tested?
This from an earlier post by another contributor:
"gatso equipment uses SMPSU's - switch mode power suply units.
SMPSU's couldn't give a flying s***e what the input voltage is like, as long as it's somewhere between 55v and 400v, with a brown out tollerence interval of (I think) at least 2 seconds. Loop resistance is also irrelevent, as long as it can supply the required VA, which is only about 200. Basically the loop resistance would have to be greater than about 40-50 ohms to affect the operation of the camera.
the output will be an absolutely rock solid 5v, 12v and -12v. Similar to a computer power supply."
What this misses is that if the power supply unit is never tested, there is no way of substantiating that the unit's output is within the specified range of tolerance. There is also the matter of reliability of these units. Some would have you believe that they are rock-solid. My own experience in corporate I.T. tells me that the output, even with carefully monitored input, can vary substantially. Indeed, there is an entire industry in I.T. monitoring power supply output, particularly to expensive server processor boards. Hot redundant power supplies exist not just for back-up on total failure, but to switch, if the output strays outside of its prescribed range.
Remember too that GATSO camera modules are calibrated on a stable, laboratory power supply.
Whilst I'm sure that the Crown can rely upon DCA to lean heavily on the Judge in a preliminary hearing to decide whether or not the expert evidence is admissible, the fact remains that CPS and the constabulary don't have an answer to this. In response to a disclosure request, CPS have declined to provide any Home Office specifications, and have even refused to forward the 'Speedmeter Handbook' referred to in the calibration certificate.
In the words of the Head of the Saftey Camera Unit, "No, we've never tested them. Nobody's ever asked that question before..."
"gatso equipment uses SMPSU's - switch mode power suply units.
SMPSU's couldn't give a flying s***e what the input voltage is like, as long as it's somewhere between 55v and 400v, with a brown out tollerence interval of (I think) at least 2 seconds. Loop resistance is also irrelevent, as long as it can supply the required VA, which is only about 200. Basically the loop resistance would have to be greater than about 40-50 ohms to affect the operation of the camera.
the output will be an absolutely rock solid 5v, 12v and -12v. Similar to a computer power supply."
What this misses is that if the power supply unit is never tested, there is no way of substantiating that the unit's output is within the specified range of tolerance. There is also the matter of reliability of these units. Some would have you believe that they are rock-solid. My own experience in corporate I.T. tells me that the output, even with carefully monitored input, can vary substantially. Indeed, there is an entire industry in I.T. monitoring power supply output, particularly to expensive server processor boards. Hot redundant power supplies exist not just for back-up on total failure, but to switch, if the output strays outside of its prescribed range.
Remember too that GATSO camera modules are calibrated on a stable, laboratory power supply.
Whilst I'm sure that the Crown can rely upon DCA to lean heavily on the Judge in a preliminary hearing to decide whether or not the expert evidence is admissible, the fact remains that CPS and the constabulary don't have an answer to this. In response to a disclosure request, CPS have declined to provide any Home Office specifications, and have even refused to forward the 'Speedmeter Handbook' referred to in the calibration certificate.
In the words of the Head of the Saftey Camera Unit, "No, we've never tested them. Nobody's ever asked that question before..."
skymaster said:
ramtec said:
Unchecked power = reasonable doubt...
You are forgetting than in the case of speed enforcement the notion of reasonable doubt is tossed out of the window like a soggy tissue. While we have a criminal justice system for most offences we have a farce for speed enforcement that has no basis in the corner stones of justice or evidence. Anyone know if ANY forces check power supplies? £70 for an annual test to prevent your officers from being electrocuted - any takers?
The standard line taken in court by the Crown is that police officers 'test' the camera modules each time they fit them in a new location. The 'test' is rarely questioned but is couched in such terms as to make the Court believe that it confirms accuracy. This is grossly misleading. Suffice to say that its's nothing remotely connected to calibration at all. It's a very basic 'does it work?' test. Pretty close to a conspiracy to pervert the course of justice, with a theoretical maximum penalty of life imprisonment.
When I told the MD of one of the UK's largest aerospace 'testing' companies, that GATSO camera modules were calibrated in the Netherlands, then shipped back to the UK, then moved from cabinet to cabinet between calibrations, he fell off his perch. He went on to explain that if the aerospace industry calibrated measuring equipment like that, not only would it be disallowed, but they would be prosecuted.
Any one know if ANY forces check their GATSO power supplies...?
When I told the MD of one of the UK's largest aerospace 'testing' companies, that GATSO camera modules were calibrated in the Netherlands, then shipped back to the UK, then moved from cabinet to cabinet between calibrations, he fell off his perch. He went on to explain that if the aerospace industry calibrated measuring equipment like that, not only would it be disallowed, but they would be prosecuted.
Any one know if ANY forces check their GATSO power supplies...?
The surprising thing is how easy this would have been to get right. A few quid each year, and you could vouch for the output voltage and the cabinet circuitry resistance AND meet your statutory obligations in keeping police officers safe.
The fact that it appears, so far, that no forces are testing power supplies, suggests that it was never in the original spec, and that in certifying the GATSO, the Home Office needs to be called to account.
My local constabularly haven't testsed a single power supply in over ten years. They allege, but cannot substantiate, that there's no need to test power supplies. On that logic, officers could be fitting camera modules to untested cabinet power supplies when the units are 25+ years old. I'd buy some rubber gloves, if I were you...
The fact that it appears, so far, that no forces are testing power supplies, suggests that it was never in the original spec, and that in certifying the GATSO, the Home Office needs to be called to account.
My local constabularly haven't testsed a single power supply in over ten years. They allege, but cannot substantiate, that there's no need to test power supplies. On that logic, officers could be fitting camera modules to untested cabinet power supplies when the units are 25+ years old. I'd buy some rubber gloves, if I were you...
Edited by ramtec on Tuesday 25th September 16:08
Edited by ramtec on Tuesday 25th September 16:08
Actually, I need a police officer to go to the HSE and ask, as a matter of personal safety, what they're doing about it. I have already fed this information to the HSE's Nottingham office, but they have declined to comment on the outcome of their investigations, citing confidentiality between them and the constabulary involved. (stinks, doesn't it?)
If I can get a serving police officer to ask the question, the HSE is legally obliged to give him / her a full response.
Anyone know yet whether ANY force tests power supplies...?
If I can get a serving police officer to ask the question, the HSE is legally obliged to give him / her a full response.
Anyone know yet whether ANY force tests power supplies...?
Edited by ramtec on Tuesday 25th September 16:28
ramtec said:
This from an earlier post by another contributor:
"gatso equipment uses SMPSU's - switch mode power suply units.
SMPSU's couldn't give a flying s***e what the input voltage is like, as long as it's somewhere between 55v and 400v, with a brown out tollerence interval of (I think) at least 2 seconds. Loop resistance is also irrelevent, as long as it can supply the required VA, which is only about 200. Basically the loop resistance would have to be greater than about 40-50 ohms to affect the operation of the camera.
the output will be an absolutely rock solid 5v, 12v and -12v. Similar to a computer power supply."
What this misses is that if the power supply unit is never tested, there is no way of substantiating that the unit's output is within the specified range of tolerance. There is also the matter of reliability of these units. Some would have you believe that they are rock-solid. My own experience in corporate I.T. tells me that the output, even with carefully monitored input, can vary substantially. Indeed, there is an entire industry in I.T. monitoring power supply output, particularly to expensive server processor boards. Hot redundant power supplies exist not just for back-up on total failure, but to switch, if the output strays outside of its prescribed range.
Remember too that GATSO camera modules are calibrated on a stable, laboratory power supply.
Whilst I'm sure that the Crown can rely upon DCA to lean heavily on the Judge in a preliminary hearing to decide whether or not the expert evidence is admissible, the fact remains that CPS and the constabulary don't have an answer to this. In response to a disclosure request, CPS have declined to provide any Home Office specifications, and have even refused to forward the 'Speedmeter Handbook' referred to in the calibration certificate.
In the words of the Head of the Saftey Camera Unit, "No, we've never tested them. Nobody's ever asked that question before..."
There you go. I think that helps with understanding why accuracy is affected. We're talking about electronic circuits, so output voltage of the power supply and circuitry resistance has preset tolerances to ensure accuracy. At the extreme, it's like asking if the radar and camera module would work properly powered by a bolt of lightning. The tolerances are wide, but if the cabinets are NEVER tested, there is absolutely no way of saying that they're within tolerance."gatso equipment uses SMPSU's - switch mode power suply units.
SMPSU's couldn't give a flying s***e what the input voltage is like, as long as it's somewhere between 55v and 400v, with a brown out tollerence interval of (I think) at least 2 seconds. Loop resistance is also irrelevent, as long as it can supply the required VA, which is only about 200. Basically the loop resistance would have to be greater than about 40-50 ohms to affect the operation of the camera.
the output will be an absolutely rock solid 5v, 12v and -12v. Similar to a computer power supply."
What this misses is that if the power supply unit is never tested, there is no way of substantiating that the unit's output is within the specified range of tolerance. There is also the matter of reliability of these units. Some would have you believe that they are rock-solid. My own experience in corporate I.T. tells me that the output, even with carefully monitored input, can vary substantially. Indeed, there is an entire industry in I.T. monitoring power supply output, particularly to expensive server processor boards. Hot redundant power supplies exist not just for back-up on total failure, but to switch, if the output strays outside of its prescribed range.
Remember too that GATSO camera modules are calibrated on a stable, laboratory power supply.
Whilst I'm sure that the Crown can rely upon DCA to lean heavily on the Judge in a preliminary hearing to decide whether or not the expert evidence is admissible, the fact remains that CPS and the constabulary don't have an answer to this. In response to a disclosure request, CPS have declined to provide any Home Office specifications, and have even refused to forward the 'Speedmeter Handbook' referred to in the calibration certificate.
In the words of the Head of the Saftey Camera Unit, "No, we've never tested them. Nobody's ever asked that question before..."
eltax91 said:
So, reading on this thread, IF your case is proven and the power supply is proved to cause reasonable doubt in front of a court, does that mean that all thos caught by GATSO could claim back their fines and sue the scamera partnerships for loss of earnings (from days in court) and/ or additional costs incurred for insuring vehicles.
If this comes off, it could mean the scameraships going bankrupt.... hopefully
The Court could rule that there is a general leaning towards accepted accuracy, unless specifically proven to the contrary. Certainly, that's what they've done when the calibration of the camera module has been questioned. However, in this case, the power supplies have never been tested, so yes, I hope it causes all involved severe pain. They f**ked with the wrong Marine...If this comes off, it could mean the scameraships going bankrupt.... hopefully
Try telling that to a processor on a server board when a power supply fluctuates.
We have any one of a number of examples from the National Physical Laboratory of inaccuracy in digital circuits being caused by errant power supplies. Sorry, I've heard all of this before, and it doesn't wash.
We have any one of a number of examples from the National Physical Laboratory of inaccuracy in digital circuits being caused by errant power supplies. Sorry, I've heard all of this before, and it doesn't wash.
This is straying from the point. GATSO camera modules will have a power input specification. However wide the tolerance, if the power supply cannot be verified as being within specification then QED the entire unit is outside of its operating parameters.
It will be an interesting preliminary hearing, since the judge will have been pressurised by the DCA (or one of those splendid 'insider' law firms) to find for the Crown, in disallowing our expert witness, but in so doing, the court will be seen to have given its blessing to the criminal negligence of the constabulary...
Any news on whether ANY forces test their power supplies yet?
It will be an interesting preliminary hearing, since the judge will have been pressurised by the DCA (or one of those splendid 'insider' law firms) to find for the Crown, in disallowing our expert witness, but in so doing, the court will be seen to have given its blessing to the criminal negligence of the constabulary...
Any news on whether ANY forces test their power supplies yet?
Edited by ramtec on Tuesday 25th September 18:56
That's an interesting point, since the alleged offence occurred just as the street lights were coming on...
...and no, there is no scheduled (or unscheduled) maintenance whatsoever of the GATSO cabinets power supply unit and its adjoining circuitry...
...and no, there is no scheduled (or unscheduled) maintenance whatsoever of the GATSO cabinets power supply unit and its adjoining circuitry...
Edited by ramtec on Tuesday 25th September 19:11
Both the radar and the camera module rely on precisely timed intervals to measure speed...
...but the issue is simpler than that. The GATSO camera module has a prescribed operating envelope for the power supply that powers it, outside of which its accuracy cannot be guaranteeed. If it requires power / resistance of the cabinet to be within a certain specification, but there is no testing, then QED the entire device cannot be deemed to be within its certificated operating parameters.
...but the issue is simpler than that. The GATSO camera module has a prescribed operating envelope for the power supply that powers it, outside of which its accuracy cannot be guaranteeed. If it requires power / resistance of the cabinet to be within a certain specification, but there is no testing, then QED the entire device cannot be deemed to be within its certificated operating parameters.
Edited by ramtec on Wednesday 26th September 08:10
Edited by ramtec on Wednesday 26th September 08:11
I have little expectation of winning, but it will be useful to follow the trail of seeing which Judge gets the case, and how they contrive to worm their way out of it.
However, I don't expect this to get to trial.
At the moment, CPS stand by "there's no need to test", and are not calling an expert witness to counter my position. Their move to have the expert witness disallowed, at the next prelim hearing, was entirely predicatable. If they don't succeed in that, I expect the case to be dropped, so that a precedent isn't set. What we're going through at the moment is a range of legal devices being used by CPS to try and avoid the inescapable: someone messed up...
However, I don't expect this to get to trial.
At the moment, CPS stand by "there's no need to test", and are not calling an expert witness to counter my position. Their move to have the expert witness disallowed, at the next prelim hearing, was entirely predicatable. If they don't succeed in that, I expect the case to be dropped, so that a precedent isn't set. What we're going through at the moment is a range of legal devices being used by CPS to try and avoid the inescapable: someone messed up...
Please bear in mind information already published in this thread:
1. CPS have offered NO substantiation (evidence - documentary or otherwise) of their claim that power supplies 'don't need to be tested'.
2. CPS has refused to supply a copy of the speedmeter handbook referred to in the calibration certificate. They claim that they have 'no more evidence to present to the court'.
3. A calibrated camera module and radar will have set parameters of both voltage supplied and circuit resistance. For the power supply and cabinet circuitry to fall within these paramenters a test WILL be required.
4. The constabulary in question has already admitted that it has "NO testing procedure" whatever - not even for Health & Safety.
You can imagine the barrister for the deceased's family in a civil suit against the police force, following the death of an officer who touched a live cabinet: "So, Chief Constable, you're telling this court that the reason that your officer was exposed to this danger was because your force had arbitrarily decided not to conform with Health & Safety legislation; and that the reason that you failed to carry out such tests was because it would have exposed you to a review of all speed camera offences? Case rests, m'lud..."
If I can remind everyone of the reason for my post:
Does anyone have ANY information that suggests that ANY force is testing their power supplies?
1. CPS have offered NO substantiation (evidence - documentary or otherwise) of their claim that power supplies 'don't need to be tested'.
2. CPS has refused to supply a copy of the speedmeter handbook referred to in the calibration certificate. They claim that they have 'no more evidence to present to the court'.
3. A calibrated camera module and radar will have set parameters of both voltage supplied and circuit resistance. For the power supply and cabinet circuitry to fall within these paramenters a test WILL be required.
4. The constabulary in question has already admitted that it has "NO testing procedure" whatever - not even for Health & Safety.
You can imagine the barrister for the deceased's family in a civil suit against the police force, following the death of an officer who touched a live cabinet: "So, Chief Constable, you're telling this court that the reason that your officer was exposed to this danger was because your force had arbitrarily decided not to conform with Health & Safety legislation; and that the reason that you failed to carry out such tests was because it would have exposed you to a review of all speed camera offences? Case rests, m'lud..."
If I can remind everyone of the reason for my post:
Does anyone have ANY information that suggests that ANY force is testing their power supplies?
Obliged to you all, and GUESS what's in the Speedmeter Handbook!
Actually, I feel outraged that both CPS and the police have said in writing and in court, in response to a formal request for disclosure that named the Speedmeter Handbook, that the Handbook was unavailable to them. I think we might hazard a guess as to why they didn't want to disclose this.
Now should I complain to the police, or the court about a conspiracy to pervert the course of justice...?
Actually, I feel outraged that both CPS and the police have said in writing and in court, in response to a formal request for disclosure that named the Speedmeter Handbook, that the Handbook was unavailable to them. I think we might hazard a guess as to why they didn't want to disclose this.
Now should I complain to the police, or the court about a conspiracy to pervert the course of justice...?
Edited by ramtec on Wednesday 26th September 17:46
Apparently, Local Authorities accept that even power supplies in street lights have to be checked on a routine basis.
How 'wrong' is not up for debate. A calibrated device fitted to a cabinet, ceases to be calibrated when connected to an untested power-supply. We can't say what the precise effect on either the radar or the timing mechanism for the camera interval was, and neither can the police. The camera module is calibrated on laboratory power, and is designed to work within set parameters of power input. The power output of the power supply hasn't been tested in over 10 years, and therefore cannot be deemed to be within specification.
...and now we find that the Crown have withheld the very evidence that delivers the defence a specification for the power supply tolerances...
Untested power = reasonable doubt...
Does anyone know if ANY forces test their GATSO power supplies?
How 'wrong' is not up for debate. A calibrated device fitted to a cabinet, ceases to be calibrated when connected to an untested power-supply. We can't say what the precise effect on either the radar or the timing mechanism for the camera interval was, and neither can the police. The camera module is calibrated on laboratory power, and is designed to work within set parameters of power input. The power output of the power supply hasn't been tested in over 10 years, and therefore cannot be deemed to be within specification.
...and now we find that the Crown have withheld the very evidence that delivers the defence a specification for the power supply tolerances...
Untested power = reasonable doubt...
Does anyone know if ANY forces test their GATSO power supplies?
Edited by ramtec on Thursday 27th September 08:11
We've had a number of emails from people warning us about the few 'people' who frequent this site that are 'insiders', and we thank everyone for their helpful input. Due to an earlier bait-laying excursion on here, we pretty much know who the 'insiders' are, so we'll only feed them that which we want them to hear.
For those of you who haven't spotted it yet, there is a deeper agenda here, which is adequately served, for the moment, by observing the contortions through which the Crown will go to gain a successful prosecution. We fully expect to lose if this ever goes to trial, but in winning the Crown will leave a mile wide trail of evidence around the real story.
Oh dear, did I just qualify myself as a subversive...?
For those of you who haven't spotted it yet, there is a deeper agenda here, which is adequately served, for the moment, by observing the contortions through which the Crown will go to gain a successful prosecution. We fully expect to lose if this ever goes to trial, but in winning the Crown will leave a mile wide trail of evidence around the real story.
Oh dear, did I just qualify myself as a subversive...?
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