On Wed, 15 Nov 2017 09:00:17 -0800 (PST), whisky-dave
wrote:
snip
They mean (clearly) 'The power distribution network'.
yeah clearly like 220-240V will give you 2KW clearly it doesn't matter what the voltage is or does it.
What do you think? P=VxI
snip
I do I can't take them apart they do NOT belong to me or my department.
I know.
So why do you expect me to take them apart ?
I don't *expect* you to, I suggested you could.
Is that what you do, you get equipemnt from new you think it faulty and you take it about so making the wattenty void ?
It depends on the situation, cost of the equipment, likelihood of
getting satisfaction and all sorts of things. Don't forget, you have
loads of these things are they aren't expensive, even if you had to
pay for one yourself.
I do NOT believe that they have a wiring fault.
I'm not interested in your 'beliefs' mate, just the facts. ;-)
And where will you get them from.....
By asking the supplier or manufacturer or failing any satisfaction
there, myself by taking the panel off.
It has a thermostat, an overtemp switch / cutout and a thermal fuse.
I do NOT know if it has a thermal fuse did you see it mentioned anywhere ?
No, but every similar device I've ever opened has had one and I'm not
sure it would get certification without.
So when would this fuse blow and why isn't it mentioned in the manual ?
When the temperature of the radiator exceeds the setting of the
thermal fuse and it's probably not mentioned because it sometimes
isn't, especially cheap Chinese gear. The reason it's not is because
when it's been activated, the chances are either something has gone
very wrong or the heater has been abused.
These are the actual terms people who know what they are talking about
use to ensure they all understand each other.
https://en.wikipedia.org/wiki/Thermostat
https://en.wikipedia.org/wiki/Therma...Thermal_switch
https://en.wikipedia.org/wiki/Therma...f#Thermal_fuse
None of which appear in the data sheet.
Two of them do, just that you don't understand enough about it all to
realise it. ;-(
No of those do, they use differnt terms.
You are *really* stupid, are trolling, lying or can't read (your
call).
http://www.farnell.com/datasheets/2339828.pdf
P3 "Adjustable Thermostat"
P4 "thermostat knob, thermostat, thermostat, thermostat .."
And if you can't work out that a "overheat protection system" isn't
covered by:
"A thermal switch (sometimes thermal reset or thermal cutout (TCO)) is
a device which normally opens at a high temperature (often with a
faint "plink" sound) and re-closes when the temperature drops. The
thermal switch may be a bimetallic strip, often encased in a tubular
glass bulb to protect it from dust or short circuit. Another common
design uses a bimetallic shallow dome-shaped cap which "clicks" to an
inside-out inverted cap shape when heated, such as the "Klixon" brand
of thermal cutouts. [2]
Unlike a thermal fuse, a thermal switch is usually reusable, and is
therefore suited to protecting against temporary situations which are
common and user-correctable. Thermal switches are used in power
supplies in case of overload, and also as thermostats in some heating
and cooling systems."
The datasheet *you* linked to.
No it says overheat protection system, nothing about thermal cutouts.
See above. " + " = 'pass' in your case in seems.
I know what's happening but I didnlt get that knowledge from the data sheet.
I repeat, you don't know what is happening,
I do.
You haven't proved it yet?
you only report what you
see happening (and are still asking us *why*).
I know why crap underspec heaters.
You know why what?
So if this heater is left on it;s doen;t produce 2KW of heat it doesn't consume 2KW of electrical power it drops to 700W
No, it doesn't consume nor (therefore) give off 2kW of heat because
the supply voltage won't allow it to.
The supply will allow it, the supply has little to nothing to do with it, it is plugged into the mains supply.
Aw bless ... it's like trying to explain it all to a child. ;-)
It IS NOT the supply that is reducing the power consumption from teh stated 2KW to 700W.
I never said it was and that fact that you have suggested I have just
about says it all.
Perhaps you're getting the overheat protection system mixed up with ohms law.
Aww, bless.
snip
Can you just have the NoII element on without
the NoI .
Yes.
and if so, I wonder if it would then still cycle on the
overtemp stat?
No idea, I would expect it to cycle a little.
Expect, why don't you try it?
But there's no cycling at 700W
Under the current conditions, no.
Don;t forget the data sheep spoec that says any voltage from 220-240 the rad will comsume 2KW ;-P
The good news is at least you (now seem to) realise that is
impossible. ;-)
New it along alone although I didn't consider it particually important for our use.
What?
What would you expect a heater with a label that says 220-240 50Hz 2000W to do ?
Consume circa 2000W at 240V and,
and yet at 212V it's consuming just 700W.
And?
if the surface area isn't big enough
to dissipate all that energy, get overly hot and trip out on it's
overtemp stat, even when the main stat is still calling for heat.
Yes my one at home claims to have a larger surface area and has coluumns for the heat to rise rather than 'hang about' but then it was about £130 (£160 now) compared to just £25.
The cost shouldn't have anything to do with it other than a lower
powered heating element would probably be cheaper and be less likely
to cause the rad to overtemp under typical conditions.
However, I think I would expect it to cut out entirely, not back to
the low power element.
That's what I would have assumed, but only if it got dangerously hot or someone covered the heater with something, I wouldnlt expect such a heater just to cut out or even reduce 'power'.
Agreed.
Do you expect your 450W to reduce to 126W after about 2 hours of being on ?
Nope. However, mine cuts down from 450 to 0W in much less time than 2
hours (even though the main stat temp hasn't been reached).
If not way not.
Because it's a single element heater so one can't 'cut out' and
therefore change the total wattage.
Yep pretty much says that in the manual and I've tried it and it works
it goes dwon to 0W consumtion when laying on it's side or rather it switchees out at about 40 degrees.
Yes, you said. If not a physical button underneath, it would often be
a ball, cup and micro switch arrangement.
Yep I know, I doubt and can't find a physical button this would be difficult to implemete on a heater with casters. I have that form of cut out on my fan heater.
Ok.
which acutally does cut out or off the electicity supply to the heater giving a reading of 0 Watts.
Yes, that is *another* safety function and only relevant to the
discussion if you knock the heater over. It cuts the power to 0, just
as the main thermostat does.
Yes I know, I've know that all along. I've had one in my office for about 2 years now.
You said 'The cut-out is the Safety tip over switch'. No one was
talking about such things (but you). I was talking of the 'overtemp
safety cutout'. You got confused.
No you were the one that got confused a cut out cuts off so there is NO overtemp cut out, because it doesnlt cut out, power remains the LEDS REMAIN ON.
What?
So it canlt be cutting out the power can it.
All the 'cut outs' cut the power, what would be the point otherwise.
The cut out is for when it tips over, as the LEDs go out they flicker too so it;s not a micro switch either, so likely a mercury or non-mercury tilt switch
Ah, like one with a ball, cup and micro switch possibly?
which does cut out the power, unlike the overheat protection which keeps the power connected.
It does not keep the power connected to the heater element does it
(which is all it needs to do for that safety feature).
snip
Yes (FFS), the overtemp switch, *not* the overtemp fuse. Really, is
this all that difficult for you?
There is NO overtemp fuse,
Ah, so you have xray vision now? Have you swapped that for common
sense and reason perchance?
it's probbly a bimetalic switch iven the price point.
What, they would fit something more expensive *and* more dangerous
because of the manufacturing cost?
It's NOT a cut out its NOT a fuse.
Of course it isn't, if you say so.
so the only sure way of getting the heater to again comnsume 2KW is to use a cold air blower (I have another fan heater) to blow cool air over the fins of the 2KW heater.
Yup, because as I explained elsewhere, the radiator is unable to
dissipate sufficient heat fast enough and so 'overheats' and trips
itself (or the just main element in your case it seems) out.
Yes trips out and auto-resets yes.
Yes, because it's an 'overtemp stat', not an 'overtemp fuse'.
It's not a fuse well done. A fuse would need to be replaced.
Mate, you are either *sooo* desperate to prove that you think you have
even the slightest grasp on this that you will try anything, no matter
how stupid it makes you look or you *really* have comprehension issues
(or are on a wind up).
For you to even stat to be able to counter me on any of this you would
have to keep track of it all and it is obvious that you can't.
Print any of it off and take to an adult and get them to tell you who
seems to have any idea what they are talking about (and I mean
*anyone* who has tried to help you here, not just me).
And while in this state it does NOT give out 2KW of heat.
No, really, why didn't you say earlier? Hey, I wonder why it doesn't
... ?
I did but you must have ignored it.
Whoosh.
Are you now just trolling mate?
All I'm saying is a 2KW heater won't consume 2KW if yuo leave it on 'full' power
It will if on a suitably rated supply and does initially.
It's always been on a suitabley rated supply.
Not for 2kW output it hasn't.
It's within the specified range.
Really?.
and does initially.
So the penny has started to drop at long last.
Nope, obviously it hasn't (with you). ;-(
How can you be so thick ?
Bless.
it will drop to 700W
So must have been higher (than 700W) or it wouldn't 'drop' would it?
well done you're almost there now.
Bless.
Nah that's for the religous.
Hey, you were the one with all the beliefs. I *know*.
Nothing to do with the thermostat (the thinbg with the knob on it) that remains at maxium setting .
Where did I mention anything about the thermostat affecting your
results? What part of 'indefinitely *until* the temperature set by the
thermostat is met' don't you get?
Clue, AFAIK, the temperature set by the main stat has *never* been met
yet.
I know, but I;ve no idea what that temerature might be do you ?
Yes, 'Maximum'. Other than that, the fact it hasn't been met is all we
need to know.
Because threr arenl;t any temperature markings like you get on typical central heating systems why do you think that is ?
I don't 'think' why that is, I know ... because the thermostat isn't
calibrated or very accurate (now you know as well!). ;-)
So, I was going to design and build a controller that uses an Arduino
Nano, a triac and a couple of external temperature sensors to properly
'manage' the heater. The std heater plugs into my solution.
Are you suggeting that the thermostats on those heaters don't work ?
Nope.
So what's wrong with the heaters then ?
Nothing. Everything is fine ... (obviously).
Temp sensor 1 will be clipped to the heater and will moderate the max
temp of the rad to less than the internal overtemp switch.
why bother.
To make it suitable for a bedroom.
Are you saying these heaters arenlt suitable for bedrooms ?
Yes, because of the noise levels.
Where did you read that in the manaul ?
There was no mention of sound levels in the manual.
Or perhaps yuor getting confused where it says it;'s OK for use with children over the age of 8. Although I have no idea where they get that cut-off from ;-P
Nope ... I thought those limits may well apply to you though.
You see most people buying these heaters arent; likey to set up an arduino
I know, especially you eh! ;-)
I certainly wouldn't buy a cheap £25 heater then spend more on a device to control it.
And I'm not? Maybe the people who sold you the autotransformer also
supply you Arduinos?
The *reason* for doing that is we only need a small heater in the
bedroom but both the overtemp stat and thermostat are quite noisy,
hence the electronic solution.
well noise isn't our concern the amount of heat supplied is more important.
No! Why didn't you say that at the beginning! ;-(
You really think a few clicks of a radiator will wake up the or so students in the lab. about 25 students at the moment.
Whoosh
Here's a link to what the lab was like do you really think a radiator click will do anything.
https://www.youtube.com/watch?v=JCBXuXBAl4g
Whoosh.
So what made you choose 450W heater ?
Because it was tiny (in size, just so you don't confuse small size
with low power).
How tiny I've had a 7805 on a TO220 heatsink reach 101C, hotter than my raidiator gets at 98C. So I can devise an even smaller heater than you have brought.
Good for you.
Doing the calculations should be step one mate, not step two.
Shouldn't be a step for me or anyone else here.
That's *exactly* who should be doing it. Or do you think CPC should do
it for you, or someone here?
It wasn't for you ?
Yes, it was.
in your own home ?,
Yes.
size was the proity for you.
Yes, because I knew that even that small would heat the room
sufficiently. You knew no such thing with the rads that were bought
for the lab (and still don't).
When we asked for heating or we'd leave the building because it was below the minium temerature and therfore the labs wouldn't run and the students would complain, they ordered 40 convections heaters for use and brought over 8 old ones as a stop-gap measure, some had broken feet and wouldn't stand up properly.
Ok ... ?
About 9 years ago we were banned from using convection heaters in labs, a few years later they banned them from labs and offices unless fixed to a wall, a year later they banned them completely due to H&S concerns.
Ok ... ?
I found it a little odd that estates, those in charge of buildings, services and maintaince didn't get this email/memo or directive.
Sounds par for the course there ...
When we told them we can't use them they cancelled the order and ordered oil filled rads which we asked for as we can use those, they didnl;t ask which ones or what type like you went for size I assume they went for cheapness,
Ok.
Only problem with them is that the mains leads aren't really long enough for what we wanted.
Ok.
Can you show yuor calculations for step 1 ?
I don't need to because the heater is more than capable of meeting the
requirements.
Poor excuse,
No excuse, fact mate.
how did you know it'd be cable of meeting the requirements.
Because I'd had an even lower wattage heater in there previously (as
used in a caravan etc).
snip
Well, one precludes the other (doh). eg (For the hard of thinking), if
it was designed to work like that it could still be a design fault but
then wouldn't be a production wiring fault.
So there's nothing wrong with them legally is there,
If you know, why are you asking me?
so no reason they can't be sold.
I don't know if the regs allow for only one element be cut out in the
event of an overheat situation?
perhaps a casual users understanding like those that ordered them who have degrees in managment but can't tell a plug from a socket.
Or determine the energy requirements of a space (and why you would
need to) or how a basic electric radiator works?
Then how would you go about such a thing ?
See the repli(es) from John Rumm.
or rather what sort of figure would you end up with ?
The energy required to attain a desired temperature assuming the worst
(realistic) case temperature outside.
And if it did you would contact the supplier and ask why eh?
That would depend on the car and the cost of that car.
Irrelevant.
Very relivant a 2CV has a 0-60 time but try getting it to pull a caravan.
We were talking trailers ... and I tow one behind my solo cycle and
behind my 200cc Messerschmitt KR200. However, it's still irrelevant as
you have no idea how much each trailer weighed.
I know you don't, in spite of me explaining it several times and
suggesting you check one yourself (wiring) and contact the supplier /
manufacturer.
Not interested when 3 of the 5 all do the same just like it says in the supplied manual.
Where does it explain in the manual that the over temp stay only works
on the bigger element?
It doesn't mention how it regualtes over temerature and more than it describes the tilt cut out.
Quite. So you are happy to assume because 3 out of 5 do the same
thing, there can't be any issues.
snip
By measuring their duty cycle at a range of (ambient) temperatures and
taking it from there.
How would you do that without first buying one ?
You can't?
Where does it mention a duty cycle, it does so why assume one.
It doesn't and because you have learned that there is. I have assumed
nothing.
Explain it to me, if you do really understand this.
See above (and there is no *if*).
there;s a really big if, you claim to be able to calculate what you need and then using that information you'd buy the correct rad.
You could if you asked the right questions. Like, 'does this heater
give 2kW continuously under std conditions'.
I would NOT be happy buying a 2KW heater just to reduce it to 1KW with a diode in the hope it didn't drop to 700W.
I'm not saying you would be happy to do that ... I was just trying to
help you understand the problem.
I know the problem crap heaters, or rather heatrs that donl;t do what they imply.
They do do what they imply, but not for the length of time you guessed
they might. ;-)
The thermostat is meant to control both the amount of current heating the eliment and therfore the amount of heat generated or whay donlt yuo explain what the thermostat is for.
Because at the moment, the main thermostat hasn't come into it as the
room hasn't reached the required temperature.
When will it reach the required temperature ?
Who knows if it ever will as you haven't done the thermal calcs.
That is the main point.
It is, as we have been saying all along.
No point in buying 2KW heaters that go down to 700W after two hours.
That may well be true, but you would have to check against the calcs.
If the average output of the rads is sufficient they could be
perfectly ok.
If I buy a 2KW heater I expect to get 2KW for as long as it is on.
Agreed, you *might*, if you were aware there were some out there that
couldn't manage that.
I'd expect the fins/metal and machnicas to be able to copy with being on for days at 2KW, if the heater is rated at 2KW.
I'd agree, and there are that can do that, but probably not for that
money or size.
If yuo look in ther manual it tells you how to set these units up using the thermostat rather than the over heat protection or the trip out.
No, does it rolls eyes, I wonder why no one picked up on that
sooner?
yuo certainly think a 2KW heater should run at just 700W.
Whoosh ..
I expect it to run at 2KW .
We know.
So how woul yuo work that out if 2KW heaters all reduce to 700W after 2 hours ?
Whoosh ...
answer the question.
Really? You measure the power consumed over a long enough period to
calculate the average.
This is the key point the point you keep missing.
I am missing nothing here mate, only the fact that you are just
trolling?
you;re the one trolling here,
What did the adult say when you showed them the printout?
why canl;t you understand that a 2KW heater is meant to give you 2KW worth of heat UNLESS it;s reached thermost temp. set
What can't you understand that I fully understand that (and always
have).
If not it should carry on at 2KW not give up and go down to 700W.
Maybe it would if you put it in somewhere cold or draughty enough?
Why can;t yuo understand such a simple thing.
What do you *actually* think I (or anyone who has tried to help you)
doesn't understand about any of this mate? I can assure you that
everything everyone has said on the matter makes perfect sense ... the
only one who seems to be floundering about like a fish out of water is
you?
What you have been given many times over is the answer to all your
questions. We can't make you understand them.
Cheers, T i m