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Comments
I see no reason why they wouldn't work on a radial.
Can't be used on the smoke alarm circuit (Aside: do they have to be mains powered or just interlinked these days?).
Clearly you can't put them on things like the fridge/freezer, oven/microwave or TV recorder circuits. Those are typically run in the downstairs ceiling (eg potentially under the bed upstairs) so the layout of those circuits would have to be checked/changed.
Why do you think it's for rings rather than radials? At 16 A it might not be worth bothering with a ring, of course.
If, hypothetically, EMF is a problem then my guess would be that rings would be more likely to cause problems than radials, particularly if there are any poor connections so the currents in the live and neutral each way round were not balanced.
It's complete nonsense to try and claim that the magnetic field produced by 50Hz mains wiring systems can have sufficient energy so as to impact on human health - the whole concept is based on techno babble
Regards
Barney
Do they think that a circuit with no load on it has a different 'energy' level than one with a load on it?
Have they ever read a science book?
How do people fall for this nonsense.
However, I'm fitting one of these basic panels -
http://www.tlc-direct.co.uk/Main_Index/Fire_and_Smoke/Fire_Detection_Systems/Fire_Detection_ESP/
Smaller, cheaper, detectors offsets the cost of the panel and the wiring for the detectors is at 24v so can just use cheap, small, easy to pull alarm cable.
Stand alone devices have no interconnection that prohibits operation in a fire
If you use a BS 5839 Part 1 system, you have to send a signal from the detector, to the panel and from the panel to the sounder - that cable would need to be fire rated rather than simple alarm cable.
Regards
Barney
A standard domestic install needs to be grade D - mains powered, battery back up, interconnected. The interconnect would normally be wired but there's no need for the cable to be fire rated (perfectly acceptable to spur the alarms from the lighting circuit). It's designed to give early warning of a fire in a small building so you can evacuate.
I'd assumed the battery back up was to protect in event of a power cut rather than destruction of power supply and the panel has a battery back up. My panel wouldn't comply with grade B or C without fireproof cable but I'd assumed it would meet D. I may well be wrong.
The whole point of stand alone units ie (Part 6) that have both the detection, power supply and sounder all in one is that they will operate up until such time as the fire gets to them - by then they have either done the job and people are out or it's too late for them
The whole point of Part 1 system is that it gives you operability - and the price you pay is the need to fire protect cable interconnects
There is no way on earth anyone is going to sign off your proposal for building control
Regards
Barney
Grade C, LD2
• Control and indication panel with battery back-up.
• Intruder alarm system may also support 12Volt smoke and heat alarms
• Optical alarms in hallways and landings, heat detectors in the kitchen and lounge
• May be wired in standard non-fire-resistant cable
• Requires a dedicated mains supply
Normally use in sheltered housing. So the question becomes is a Grade C system is an 'upgrade' to a Grade D system. In my naivety I'd assumed is was since the usual description of the domestic requirement is 'a minimum of Grade D'
Potentially not too late to change but getting increasingly difficult
There is without doubt 'something' happening about EMFs and a whole lot more, and this is in fact not unknown to Science, as many scientists attest, chapter and verse.
Personally, I do feel mildly enervated after a day surrounded by office electronics, and wonderfully enlivened when there's a power cut. My partner can barely enter my office to dictate her emails, and I know others whose life and health depends on getting as far away as poss from electricity, wifi, mobile phones and into non-reception areas i.e. deep Dartmoor. It's plain insulting to claim this is all imaginary.
Any 'natural philosopher', the precursor of 'scientist' would have been instantly curious about any such apparent phenomenon. Today's conservative-minded scientists should be ashamed. Personally, only with great reluctance, seldom used, and battery removed when not Me, inevitably, but live and work outside reception area I object to my own, but unfortunately in a rented property ... No neighbours, no Wifi here, not least because it won't go through 700mm thick cob walls feels yucky, not just because of vicarious invasion, but prob physically Me, loved it, but other certainly do 'feel' it, but you'd prob deny that
Hence, all radial, from individual isolators - certainly not ring. Cables cross each other at right angles, to minimise induction.
Humans have been exposed to magnetic fields several orders of magnitude greater than experienced from 50Hz systems - we live on a big magnet.
Regards
Barney
b) frequency for a start
c) most probably other factors you'd no doubt consider woowoo.
So you would say, face to face with 'my partner' and 'others I know', that they're just imagining EMF effects? Good luck!
I'm not so convinced that these EMFs themselves have a health effect, but I'm sure the symptoms are real enough.
Perhaps it's due to the stress that the electronic objects are associated with? e.g. whirring fans, misc beeps, WORK, WORK, WORK, politics etc.
Of course if someone were to do a decent double blind test....?
http://who.int/peh-emf/publications/facts/fs296/en/
“Studies on EHS individuals
A number of studies have been conducted where EHS individuals were exposed to EMF similar to those that they attributed to the cause of their symptoms. The aim was to elicit symptoms under controlled laboratory conditions.
The majority of studies indicate that EHS individuals cannot detect EMF exposure any more accurately than non-EHS individuals. Well controlled and conducted double-blind studies have shown that symptoms were not correlated with EMF exposure.
It has been suggested that symptoms experienced by some EHS individuals might arise from environmental factors unrelated to EMF. Examples may include “flicker” from fluorescent lights, glare and other visual problems with VDUs, and poor ergonomic design of computer workstations. Other factors that may play a role include poor indoor air quality or stress in the workplace or living environment.
There are also some indications that these symptoms may be due to pre-existing psychiatric conditions as well as stress reactions as a result of worrying about EMF health effects, rather than the EMF exposure itself.”
I would say exactly that, Tom, in relation to 50Hz systems up to all voltages used for distribution and transmission at any credible harmonic multiple
Spending £150 notes on a simple contactor, per circuit to solve a non technical problem is just barmy.
If you want to spend the money to feel better then fine - but let's not then promote the item as having worth - because then it becomes akin to tiger powder
Regards
Barney
You missed out the recent Aurora and solar flares.
Why do you think that science is a quasi religion? I don't know of any scientists that think that, and I know quite a few.
For an interesting take on science, listen to this. It is about climate science, but sums up why people miss the point about what is being said.
http://www.bbc.co.uk/programmes/b05nvdv4
Ed
I think the last sentence sums it up.
Director of Exeter Univ Dept of Complementary Medicine conducts one impecable scientific experiment after another to prove e.g. that homeopathy is no more efficacious than placebo (so gimme placebo!). I have it on good authority that he secretly intends this to give fuel to the growing opinion that that's what Scientific Method says, then there's something wrong with Scientific Method!
Design your own experiment, conduct it, get it reviewed, get it repeated, and those results reviewed, publish the results, including the negative ones, wait a few years and your ideas may get accepted. This is known as rigour and robustness.
Or alternatively, accept that the above has been done and you just don't like the answer (a polite why of saying stop talking bollox).
Are you talking about Bill Truble's 2011 FoI request when Professor Ernst announced his retirement?
When discussing anything medical, read Ben Goldacre's (mother is a good singer) books and find out just how terrible the research and peer reviewing has been in that area. Things do seem to be changing in that field now.
Going straight to "pre-existing psychiatric conditions as well as stress reactions as a result of worrying" is an unworthy extension of the experimenter's brief, evidence of pre-framed attitude.
How about instead proposing further lines of investigation, with intention of getting to bottom of something that clearly exists? That would be worthy of a scientific mind.
Clever people in the field have already done what you suggested and found nothing.
There is generally two parts to this sort of thing. The cause/effect and the testing/reviewing.
If you are convinced that it is 'something else' you have to go out and find it, it is not up to others to do it (because they have and found nothing).
The mechanisms behind the effects do not always have to be fully understood, but they have to be testable and repeatable. It is the repeatability that is important is this sort of research.
Then you have to be careful about what you are actually observing, a 1/20 failure rate can mean two thing. I in 20 of the experiments failed, or 1 in 20 of the subject reported a negative finding. They are not always the same thing.
What vested interests are threatening friend Grahame - for what purpose, to what end, what is the objection to ?
Or is this another of those fantastical conspiracy theories
Regards
Barney
Paul in Montreal.