ABC Inventors - electrical safety device

you cant do that for $1.50
You could do it for $1000.
true.
for that matter - if his magic device is INSIDE the
true, its pointless . they wont build the hair dryer to do it.
He would have tested two wire hair dryer in a ceramic vanity basin with plasic pipes. Do you see any thing for an RCD to detect ??
Now take a three wire hair dryer. There's water between active and earth. I see an RCD trigger.
The protex is only working because its requiring the third wire in the hair dryer.
Stick to the RCD and combine the protex into it.
That would make it a "RCSVD " Residual current or stray voltage device.
yes, quite correct.
Yeah he will save the world, but only if the RCD disappears.
all mass produced things cost $1.50 to make. whats the actual sale price ????
none at all.
this leads to the result that the protex is not as good an RCD, you should have RCD's first and then protex if you still want more protection.
The protex may as well be added to the function of the RCD
RCSVD.. Residual Current Stray Voltage Device.
Reply to
Brad Hogan
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"Brad Hogan"
** Not at all - the mere presence of water inside the appliance will cause tripping, no need for a person to be the conductor. Plus the AC power is cut off very fast - faster than an RCD that takes 30mS.
** You have not understood the principle at all.
A Class 2 appliance is not an electrocution risk unless wet or submerged - in either case the Protex will have isolated it before it could do any harm.
............ Phil
Reply to
Phil Allison
Are you joking? DOUBE INSULATED is a construction standard for electrical devices.
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John G

Wot's Your Real Problem?
Reply to
John G
active
have
the
I agree. The group of people killed mostly these days by electricity is electricians and that is due to the widespread deployment of RCD's. What's the chance of having a hand basin full of water and dropping an electric shaver into it. NIL. You wouldn't have a handbasin full of water if you are using an electric shaver. derrrrrrr!!!
There is more chance of this happening to you.
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Cheers.
Reply to
Chris
I dont see how you could safely use a Triac to switch OFF the mains in a safety product like this. for one, triacs still tend to leak a bif of voltage even when off, and when triacs (and many such SS devices) fail, they tend to go short circuit rather than open circuit. I have heard of people in swimming pools being electrocuted by very low voltages such as 12 or 24v, so even small leakage occuring through the bathwater (specially if its possibly made even more conductive than normal tap water by "contaminants" like skin oils, dirt, soap, shampoo, bath salts and such)
Also, when used in things like hairdryers, toasters, kettles and such domestic heating appliances (as shown in the "inventors" video) the current being drawn could easily be the full 10 amps, and assuming there is a 0.6v voltage drop across the triac, that would mean power dissipation of around 6w !
Triacs (used in typical cheap light dimmers) also tend to die (and internally short) very easily with surges caused by incandescent bulbs blowing and such.
Again, this is only my thought, but if you absolutely HAD TO have the mains shut off at such a lightning speed, and you needed a triac or such device to do it - the mains would have to be also then cut out by a relay as a back up as well. (and/or some sort of "crow bar" circuit as well) At least then - even in worst case and the triac shorted and didnt open the circuit - the relay backing it up would do the job a fraction of a second later when its contacts finally opened.
Reply to
KLR
My point is that the current has to flow through your heart to have any chance of killing you. Either from one arm to another or from one arm to a leg, or through your brain somehow. That is why the old trick of working on high voltage with one hand behind your back actually does work when working with high voltage supplies that are not referenced to ground such as high voltage secondary windings on a transformer etc.
Frilly fact time. Did you know that hospitals use isolated power supplies, and therefore do not have an active or neutral? Touching either side of the power points (one at a time) will not hurt you at all.
Not that I have done the research but I bet most deaths caused in this way occur when a parent goes to pull out the hair dryer while it is still in the bath tub before turning it off at the power point. -- without an RCD fitted to the mains of course.
Reply to
Heywood Jablome
"Chris"
** How come RCDs only kill electricians ???
Vengeful little suckers are they ???
** Very high.
** Rot - shaver isolation transformers are sold because of exactly this risk .
** A. What a limited knowledge of shaving you have.
B. The shaver may fall in the basin when not in use but still live.
........... Phil
Reply to
Phil Allison
Well why don't you try it for yourself and post the results
Reply to
Kate Fights, I Cry
Go to this video (the link above in the OP's post ) - and take a look ^carefully^ at where he dunks the live light bulb/socket into the tupperware container of water
If you look carefully - it appears to me to be a 3 pin moulded plug, and the short length of cord its on also appears to be 3 core round (about 7.5amp appliance cable)
(IE: it has an earth in it ? !!)
Is there a loose (earth) wire hanging out the end of that cord and therefore making it work like an everyday earth leakage unit ???
Reply to
KLR
On Thu, 05 May 2005 08:51:11 GMT, Dave Goldfinch put finger to keyboard and composed:
But the ABC URL claims that he has built it "into a home?s electrical power box or switch board", which amounts to the same thing. And if you saw the demo you would have noticed that the device was external to the appliance, so unless there was a third wire, there would have been no way to sense the voltage on any metalwork ... as you have said.
Here is some sketchy info:
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"Protex is unique according to its manufacturer because it does not rely on an earth to operate.
Protex is compatible with both ac and dc voltage from 12V dc to 415V ac and works on all electrical equipment, whether Class 1, 2 or 3. About the size of a matchbox and with minimal moving parts, the switching technology can be readily incorporated into existing electrical equipment."
There is a photo, but I'm not sure what it all means.
- Franc Zabkar
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Reply to
Franc Zabkar
On Thu, 5 May 2005 18:26:32 +1000, "Heywood Jablome" put finger to keyboard and composed:
According to my reading of the info at the ABC website, Protex is claimed to protect an individual should he simultaneously grab both A and N conductors while being perfectly insulated from earth. Clearly this is impossible.
The info is also contradictory:
"If a person comes into contact with the active and neutral conductors while handling faulty plugs or appliances, the safety switch will not detect this contact unless there is also an avenue for current to flow to earth. The current flow to earth comes from 3-pinned appliances, or what the industry refers to as class 1 appliances."
"If you use a 2 pin, non-earthed appliance you or your surroundings have to become the connection to earth to make a safety switch operate. The level of electricity that is likely to go through you depends on your surroundings and the level of electricity flowing through an appliance."
- Franc Zabkar
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Reply to
Franc Zabkar
On Fri, 06 May 2005 01:07:57 +1000, KLR put finger to keyboard and composed:
Maybe the secret to the device is in its configurability? Perhaps it is configured as a normal RCD for earthed 3-wire appliances, but uses an extra wire in the case of 2-pin appliances to sense the voltage on the metal parts.
- Franc Zabkar
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Reply to
Franc Zabkar
"Franc Zabkar"
** There is no evidence that the Protex device is an RCD - but IS a voltage sensing trip just as claimed.
The version that uses three wires merely senses voltage on the earth wire ( having interrupted that wire by inserting an impedance) and hence current flow in the earth wire. It likely trips at the usual 20 - 30 mA.
This, however, fails to work in situations where the current is flowing to other than the AC supply earth wiring - so does NOT perform the safety function for human life or fire protection that an RCD does.
Safety devices ( ie circuit breakers) that sense current flow in the supply earth have been around for decades but are ( AFAIK ) only used in industrial situations.
........... Phil
Reply to
Phil Allison
Like yourself Franc, I was flabergasted when this so-called :invention" came up on The New Inventors. The inventor sounded as though he didn't have a clue about ac electricity or its mode of operation in a domestic situation. Worse still, the panel were totally clueless and seemed to respond purely from the point of "if it promotes safety (apparently), then it must be good". And, if he really wanted to demonstrate how safe the device was using his toaster set-up, why didn't he actually poke a metal knife into the toaster with his bare hand? Using a test switch to simulate such a case of stupidity was a cop out as far as I was concerned.
Also, since the relevevant state electrical codes all require RCD's to be fitted in the main distribution box of all new buildings on both GPO and lighting circuits (have done for many years now), and there are approved portable RCD devices and extension cords already on the market, I can't see the rules changing to do away with them in favour of Protex or even to add Protex in conjunction to an RCD. Frankly, I can't see this device ever getting off the ground. I can't imagine the inventor of ever convincing appliance manufacturers to actually incorporate it into their products either and I can't see any manufacturer agreeing to include it no matter how cheap it is. Just imagine the situation where a toaster (for example) having one of these devices in it, still managed to electrocute a user. The court case would be interesting I think.
I tend to agree with Phil's assessment of the device's mode of operation.
Reply to
Ross Herbert
"Ross Herbert"
** Surely a hair dryer, shaver or heater that can boast complete safety even when very wet or submerged has an edge marketers can use.
A phrase like " Bathroom and Kitchen Safe Appliance " might be used.
Folk are already aware of the danger posed by the sort of water related accidents being referred to.
BTW:
RCDs may be installed now in all *new* premises - but so what ??
90 % of premises are old and do not have to have one !!!
In NSW one can fully renovate a premises, including rewiring and the **NOT** have to fit an RCD - until this rule is changed a million older houses, flats and units will NEVER get them.
** Just my "two cents" worth of surmising - you know.
............ Phil
Reply to
Phil Allison
But this claim would tend to convince people that they would be totally protected from electrocution and it would be difficult to prove in practice. A manufacturer would be afraid of the litigation if someone was electrocuted and he had a label saying "Bathroom and Kitchen Safe" on his product. How does he guarantee that an insulation breakdown or moisture ingress on the input side of the device can not occur such that this claim would be compromised? That's why a court case would be interesting. They would far prefer not to be involved in the safety device aspects of electricity.
True, but that's why I referred to the "portable" RCD items already on the market. I accept that the user must make a pro-active decision to actually use one of these however, and they might simply forget to. A permanently wired safety device is preferable of course, but I would predict that Protex will produce so many false trippings that it will be like the boy who cried wolf and people will probably disconnect them.
Different states have different rules. In WA any old house (pre RCD) being renovated and having new electrical work performed has to have the main switchboard upgraded to include RCD's. At least that's what my electrician told me back in '95 when I did some major renovations.
But you also have some valued technical knowledge which makes sense.
Reply to
Ross Herbert
"Ross Herbert" Phil Allison
** Optimists misconstrue all the time - but the law does not back them up.
** All product makes have Liability Insurance - long as the claim is not false or misleading they are covered.
** The claim merely refers to the existence of the safety trip device. There are recognised standards for water proofing and insulation that if complied with protect a maker from blame. Certainly the cable, its anchoring and the device need to be waterproof - this is the product maker's job to get right and get type approved.
The Protex apparently has no safety approvals at present - it is a non starter until it has got them. However, it would be wrong to assume it is not possible.
** But they are NOT being widely used in homes and nor are ever likely to be.
One cannot claim that RCDs are already providing adequate protection to the Australian public.
** Huh ?? Forget to ??
** But in millions of domestic premises it is simply NOT there and will not be in the foreseeable future.
** You need to explain this "prediction" - it a brand new one.
** In QLD, when premises change ownership an RCD must be fitted - at least this ensures statewide RCD protection in the next 20 years or so.
But whatever the case - there are still millions of unprotected premises.
One cannot claim that RCDs are already providing adequate protection to the Australian public.
............. Phil
Reply to
Phil Allison
I can see where this is going so I don't intend to respond further.
SNIP
Reply to
Ross Herbert
"Ross Herbert" "Phil Allison"
** When digging oneself into bottomless pit - it is wise to know when to stop.
.............. Phil
Reply to
Phil Allison
On Fri, 06 May 2005 02:09:31 GMT, Ross Herbert put finger to keyboard and composed:
My overall feeling at the time was one of frustration. Very little info was divulged, and the demo wasn't explained very well. Since then I've become even more frustrated by the seemingly contradictory info on the ABC's web page. The inventor's annoying website did nothing to help matters, either. It seems he is being deliberately vague and overprotective.
I wouldn't have expected him to do that, although I would have liked some indication as to the sensitivity of the device. One question I would have asked was, how does the Protex compare with an ELCB that trips at 30mA?
I could see it being integrated into some bathroom and kitchen appliances. And after seeing the demo with the submerged light, I'm reminded of the time rainwater filled the light fitting in my rented house.
Yeah, it looks that way. But how do you explain the claim that the device could be fitted to existing meter boxes? Would the device be protecting appliances within the house, or would it be detecting water in the meter box itself?
I would also question whether static electricity could trip the device. Still another problem could be appliances like my 2-pin TV where the 0V reference on the DC side of the circuit is connected to AC via a high impedance RC combo. I sometimes see a spark, or feel a tingle, when interconnecting such appliances.
- Franc Zabkar
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Reply to
Franc Zabkar

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