Electric blankets, Gratuitous complexity??

OK.....

So ahm happier'n'a alcoholic workin the night shift in a Jack Daniels 
distillery....   with my 400# deep cycle battery, 1500 W inverter (sitting 
in the back seat of m'truck), and my brand new blue electric 
blankey-poo.....
Now I can curl up in a fetal position -- in m'truck -- in compleat toasty 
comfort.....

Now, don't ax me WHY I gotta curl up in a fetal position -- in m'truck. 
Just suffice it to say, if you had my yob, you'd be curling up in a fetal 
position in YOUR truck, too.

Except for one thing.....
   My g-d electric blankeypoo dudn't WORK with my 1500 W fukn inverter!!!!! 
WTF??????

And the reason quickly became clear:  some electronics don't work with 
modified (read: shit) sine wave power.
But, what electronics are in a g-d electric blanket???

So I take apart the three-heat controller, and lo and behold, the goddamm 
thing looks like the motherboard of a small PC....    holy shit....   for a 
$25 blankeypoo????

Tryna sleuth out the ""circuitry"" of this electric blanket reminds me of 
the two days I spent tryna fix a $2.00 flashlight....  unsuccessfully.... 
holy shit....
The blanket has three wires between it and the controller, but only two of 
the wires register continuity!!  From which I surmised, via advanced Ohm's 
Law, that there is only one element in the blanket, and the controller 
actually does control voltage/current, ie, no switching among elements, cuz, 
well, there's only one element.
.
AND, the resistance is in fact the "right" resistance, cuz the wattage is 60 
W (1/2 amp), and the ohms measure 230.

So now I got an extree wire that I don't know wtf it does, amidst my awe of 
all this goddamm gratuitous complexity.

Now, I do have an inkling surrounding this latest Conspiracy of Gratuitous 
Complexity -- whose fundamental purpose is, of course, to assfuck the entire 
Global Population up to their collective ileocecal valves, so that Orwell 
looks like summer fukn camp.
It appears that this particular example (this blue electric blanket) of 
Gratuitous Complexity has to do with.....   <shudder> <shudder>  SAFETY!!!!! 
And of course the li'l CHILDREN.......

   Btw, a brief digression:
   You DO know that they now make crawling helmets for toddlers???   Yes 
indeedy, google    helmets for babies crawling    ,  and pick your link.
Better yet, ORDER yours, right away, so's when you take the li'l future Wall 
Street predator-to-be to Montessori for his (first) pre-school interview, 
you'll be showing up correck.
You yourself and the spouse should also wear matching bicycle helmets, as 
well, just to show Montessori that the whole Beaver family is indeed 
correck.....

Back to this g-d blanket bidniss....
    This shit blanket, for safety (it is UL listed btw), SHUTS OFF 
automatically EVERY GODDAMM  HOUR!!!!WTF?????

I mean, look, the g-d blanket is a *whole 60 effingW*!!!!   My goddamm BODY 
puts out more heat than that....
fyi, Your BMR of about 1 cal/min is actually nearly exactly 70 W of heat.... 
which is why 10 blustering assholes in a meeting room make the place so 
goddamm hot.

So some dumb QA engineering fuckhead sed, Oh, OH, 60 W -- spread over **24 
sq ft of g-d blanket**, no less -- is MUCH too dangerous!!!!
Sheeit, in that case, my 70 W of body heat puts me at risk for 
self-immolation, right???

Fuuuuuuuck, they couldn't have timed it for 8 hours??  6 hours????  4 
hours?????   WTF???????

So now, some while after the blanket shuts off, I'll freeze my goddamm ass 
off, have furtive nightmares, wake up, and flail around for the controller, 
just to reset it.
So now I can't even g-d SLEEP worth a goddamm, in my fetal position -- and 
if you knew how long it takes me to get in that fetal position (in m'truck), 
you'd realize this is really a significant issue.

OK....  so NOW ahm gettin it:
    SAFETY, and our precious li'l bratty g-d CHILDREN, require a solidstate 
automatic safety controller.  Shitty li'l dropping resistors, or a xsformer, 
or split heating elements, just won't do it anymore.
Now, they got a g-d controller in a $25 electric blanket  that could have 
gotten Neil Armstrong to the g-d moon.

Well, let me tell you, no one, but NO ONE messes with Angst's fetal 
position/sleep....

So I took that controller off (via the detachable connector) and 
hard-wire-crimped a shit 18 ga wire with a shit 99c-store two-in-a-pack 
unpolarized plug, so now's I got *60 uninterrupted W* of blazing power, 
blasting thru my li'l blue blankeypoo.  What a fukn triumph.....

My gripe against Gratuitous Complexity harks back to my erstwhile 1971 
Datsun 510, which got better gas mileage than almost every effing car out 
here today, ceptin Volts'n'Prius'n'shit, and mebbe that VW TDI motor....
AND, I could fix it my goddamm self.
And I think I drove around Hawaii about 25 g-d times in a Datsun B-210, on a 
gallon of gas.

Now, cars are so fukn complicated.....

HOW COMPLICATED ARE THEY???????

Cars are so fukn complicated, that factory Toyoter mechanics make more money 
than asshole college puhfessuhs.....  AS THEY RIGHTLY SHOULD, cuz college 
professors are just absolutely fukn useless.   goodgawd.....  What a sham 
the college credit is, and a bankrupting sham at that.

Cars now weigh 50% more than in the 70s....  and you can't even adjust the 
g-d IDLE!!!!
Well, you can, I spose, with a laptop and about $1,000 worth of g-d 
programming.....

Part of the Conspiracy behind Gratuitous Complexity is, imo, the desire to 
shut out the small entreepreeneer, bidnissman.  A good fraction of the 
people on these ng's could *make their own perfectly navigable electric 
car*, with a welder, lathe, milling machine, some fukn batteries and a 
motor.  Or mebbe just a welder, drill press, and an angle grinder....
But fukn Chevrolet and Nisan barely got *their* electric cars out, the 
regulatory ante is so goddamm high.  Near $40K for a g-d electric motor and 
a bunch of g-d batteries....

So, inyway, Angst finally has his new blue blankeypoo blazing away, and I'll 
be fellatingly positioning myself in peaceful bliss tonite, in m'truck, with 
my 400# marine battery/1500W inverter right behind my blissful head.

Oh shit, did I say "fellatingly"???  That would be "fetally",  "fetally 
positioning myself in peaceful bliss".....
-- 
EA

On 10/11/2012 11:01 AM, Existential Angst wrote:
> OK.....
>
> So ahm happier'n'a alcoholic workin the night shift in a Jack Daniels
> distillery....   with my 400# deep cycle battery, 1500 W inverter (sitting
> in the back seat of m'truck), and my brand new blue electric
> blankey-poo.....
> Now I can curl up in a fetal position -- in m'truck -- in compleat toasty
> comfort.....
>
> Now, don't ax me WHY I gotta curl up in a fetal position -- in m'truck.
> Just suffice it to say, if you had my yob, you'd be curling up in a fetal
> position in YOUR truck, too.
>
> Except for one thing.....
>     My g-d electric blankeypoo dudn't WORK with my 1500 W fukn inverter!!!!!
> WTF??????
>
> And the reason quickly became clear:  some electronics don't work with
> modified (read: shit) sine wave power.
> But, what electronics are in a g-d electric blanket???
>
> So I take apart the three-heat controller, and lo and behold, the goddamm
> thing looks like the motherboard of a small PC....    holy shit....   for a
> $25 blankeypoo????

It's probably a triac style dimmer circuit - likely the cheapest way of 
making a three-heat electric blanket these days. It would indeed fail to 
work with a modified sine-wave.

Sylvia.

Sylvia Else <sylvia@not.at.this.address> fired this volley in 
news:ag5ks6F1n27U1@mid.individual.net:

> It would indeed fail to 
> work with a modified sine-wave.
> 

You'd have to explain that in a lot of detail for me to believe it.

Please do.

LLoyd

On Fri, 9 Nov 2012 19:01:11 -0500, "Existential Angst"
<fitcat@optonline.net> wrote:

>
>And the reason quickly became clear:  some electronics don't work with 
>modified (read: shit) sine wave power.

Well-known inverter - and cheap generator - gotcha.
I mentioned it in one of these "inverter" posts regarding furnace
control boards.  Too bad you missed that.
Only way to avoid the gotcha is to pay up for pure sine wave.

On 10/11/2012 11:23 AM, Lloyd E. Sponenburgh wrote:
> Sylvia Else <sylvia@not.at.this.address> fired this volley in
> news:ag5ks6F1n27U1@mid.individual.net:
>
>> It would indeed fail to
>> work with a modified sine-wave.
>>
>
> You'd have to explain that in a lot of detail for me to believe it.
>
> Please do.
>
> LLoyd
>

Such circuits typically prevent current from flowing at all within a 
half cycle, until a point is reached where the remainder of the half 
cycle would deliver an amount of energy that would, if delivered over 
the entire half cycle, represent the desired power. Once triggered, the 
triac conducts until current drops below some smallish threshold.

A circuit designed to do that with a sine-wave is going to be somewhat 
thrown by an input that is a modified sine-wave.

Sylvia.

Vic Smith wrote:

> On Fri, 9 Nov 2012 19:01:11 -0500, "Existential Angst"
> <fitcat@optonline.net> wrote:
> 
> 
>>And the reason quickly became clear:  some electronics don't work with 
>>modified (read: shit) sine wave power.
> 
> 
> Well-known inverter - and cheap generator - gotcha.
> I mentioned it in one of these "inverter" posts regarding furnace
> control boards.  Too bad you missed that.
> Only way to avoid the gotcha is to pay up for pure sine wave.

  Or, just put a small transformer on the affected device.

Jamie

On Fri, 9 Nov 2012 19:01:11 -0500, "Existential Angst"
<fitcat@optonline.net> wrote:

>OK.....
>
>So ahm happier'n'a alcoholic workin the night shift in a Jack Daniels 
>distillery....   with my 400# deep cycle battery, 1500 W inverter (sitting 
>in the back seat of m'truck), and my brand new blue electric 
>blankey-poo.....
>Now I can curl up in a fetal position -- in m'truck -- in compleat toasty 
>comfort.....
>
>Now, don't ax me WHY I gotta curl up in a fetal position -- in m'truck. 
>Just suffice it to say, if you had my yob, you'd be curling up in a fetal 
>position in YOUR truck, too.

Know why a guy gets excited by a woman dressed in leather?

Because it makes her smell like a new truck.


-- 

John Larkin         Highland Technology, Inc

jlarkin at highlandtechnology dot com
http://www.highlandtechnology.com

Precision electronic instrumentation
Picosecond-resolution Digital Delay and Pulse generators
Custom laser drivers and controllers
Photonics and fiberoptic TTL data links
VME thermocouple, LVDT, synchro   acquisition and simulation

Jamie wrote:
> Vic Smith wrote:
> 
>> On Fri, 9 Nov 2012 19:01:11 -0500, "Existential Angst"
>> <fitcat@optonline.net> wrote:
>>
>>
>>> And the reason quickly became clear:  some electronics don't work with 
>>> modified (read: shit) sine wave power.
>>
>> Well-known inverter - and cheap generator - gotcha.
>> I mentioned it in one of these "inverter" posts regarding furnace
>> control boards.  Too bad you missed that.
>> Only way to avoid the gotcha is to pay up for pure sine wave.
> 
>   Or, just put a small transformer on the affected device.
> 
> Jamie
> 

OR stick a small battery back-up like you use on a computer. They smooth 
the AC and filter it as well.

-- 
Steve W.

> =A0 =A0My g-d electric blankeypoo dudn't WORK with my 1500 W fukn inverte=
r!!!!!
> WTF??????
>
> And the reason quickly became clear: =A0some electronics don't work with
> modified (read: shit) sine wave power.

I noticed the same thing during the recent power failure..

The electronically controlled electric blanket will not run on my
modified sine inverter.

I think the third wire might be connected to a thermistor or
temperature sensor in the blanket that the controller uses.

If you don't mind wrecking the controller, you could wire the heater
directly to the plug and use it on high...  or wire in a switch with a
diode and have full and 1/2. That would also defeat the timer
function. Also beware this also might disable the overheat safety
feature.  I'd include a thermal fuse if I was going to do that.  It's
no fun waking up on fire.

I'm thinking about designing a filter that will round off the modified
sine enough so that the blanket can work with the inverter.

Mark

Sylvia Else <sylvia@not.at.this.address> fired this volley in 
news:ag5mgpF21h6U1@mid.individual.net:

> Such circuits typically prevent current from flowing at all within a 
> half cycle, until a point is reached where the remainder of the half 
> cycle would deliver an amount of energy that would, if delivered over 
> the entire half cycle, represent the desired power. Once triggered, the 
> triac conducts until current drops below some smallish threshold.
> 
> A circuit designed to do that with a sine-wave is going to be somewhat 
> thrown by an input that is a modified sine-wave.
> 

I'm fully aware of how SCR and Triac (or generically, Thyristor) 
"dimmers" function, and how to build them (from scratch, without any 
supplied schematic).

I'm also aware that a "modified sine wave" or "simulated sine wave" would 
satisfy the needs of most of that type of circuit, with the exception 
that the initial triggering and the the subsequent "near zero"-crossing 
cutoff might occur late and early, respectively, from where they ought.

Such circuits don't work nicely on square waves, primarily because they 
don't have time to properly turn off.  There's usually some capacitance 
in the gate circuit (sometimes driven by a diac) that prevents a very 
rapid change from full voltage through zero to the opposite polarity  
from lasting long enough below the quench voltage for the device to turn 
off.

Such _can_ be the case with a simulated sine wave, where the voltage 
might go from (say) +10V-0--10V on a square edge.  But most inverter 
companies realized a long (long) time ago that doing it that way causes 
problems, so they switched (pun) to a waveform that stays at zero long 
enough for such devices to turn off properly.

Only a really old, or really cheap Chinese inverter would not have that 
feature.  For all I know, he has both AND a cheap Chinese blanket that 
didn't take into consideration the problems it might see on old Chinese 
inverters.

But it's not the case that simulated sine wave inverters universally 
cause problems with thyristor switches.

LLoyd