Uhhhhhhb
Purhaps you could articulate your objections more clearly?
I defined plugging the mantle into a variac as sub-optimal, and gave two better ideas.
Is non-trivial to decode, and you’ve aimed it equally at using the auto-tune on the mantel (per the fine manual) & using a temp controller that allows the heating power to be modulated.
The heating band requires x amount of voltage and amps. When you reduce it the band requires more wattage from the source to heat up adequately. It basically cooks and it will also cool any intermediate things hooked up to it in series to the heater. Those components struggle for wattage to opperate under lower voltage or amps.
ok so I hear this idea of heating mantles are not good under reduced voltage.
I have put that they are made form some kind of resistance wire with some insulation
and if your lucky a thermocouple for temp measurements.
then I give you heap of basic math to prove my point.
having pulled a few of these apart and made them from scratch please explain why
you say what you do and don’t say band requires more wattage.
what are you saying the band is made from ?
explains nothing.
now should some one have a control circuit in there mantle like the hard shell sets with the nobs
on them well unless you isolate this circuitry yes you will get interferience from it and yes it will
burn.
that is not a heating mantle that is a mantle with controler.
so can you please explain how low voltage will burn out a nichrome or kenathal wire that is insulated.
or are you thinking of something other than this being a mantle.
I am not a big fan of the I sell shit so I know shit or use the most expensive brand as that way
I know its the best (often not true to be honest)
can you explain the inner workings of the device and how you burn out the device low volt.
now having had a bit to do with electronics and have some understanding pnp and npn transitors
and doped semiconductors.
yes if you have a control circuit and you put reduced voltage in some of them they dont get
enough power to open the circuit through or not enough power for forward drop.
we see this when measuring some diodes and other semi’s with a digital multimeter
and that gives a open circuit for what would have been a closed circuit if there was enough
power to open the device you were testing. this in turn generates heat as the energy turns to work
and generates heat
here we are talking milli watts.
the thought that 300 + watts would go through one of the semiconductors is funny as if that
was the case the semi would have to be huge to deal with the heat generated.
are you calling the controller the mantle as well then ?
calls for the heating mantle ON all the time, connected to a POWERSTATor VARIAC.
straight out of glas coll instructions.
I am more than happy to admit when I am wrong and actually glad when some one gives me
new knowllage (this can be seen in some of my previous posts where I thought one thing and
found it to be wrong latter. I even correct my self if I find the mistake)
I find the attitude that a sales rep with a one liner of its going to cause fire with not proof
or explanation after I have gone to he effort to explain the underlying electronics happening
rather insulting to be honest.
so with some effort as the question this thread was based on was a valid one and does
deserve some kind of effort to answer and educate the asker.
I will not insult your person I will try to endevour to give proofs were I can when I argue against
someone elses comments as I don’t believe what others say I believe in science.
soooo for the sake of being professional and showing knowllage .
EXPLAIN
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and as 1 reference is no way to prove anything
Heating mantles produce their heat by converting AC voltage. The intense energy draw needed to generate the high degree of required heat, can blow fuses or melt socket wiring. For this reason, heating mantles should never be plugged directly into a wall socket. Instead, a transformer, such as a variac, or some form of electronic relay or switch, should be used between the heating mantle and the wall socket.
heating mantle controlled by 250w variac
The flask was heated by a Glas - Col heating mantle controlled with Variac .
so after using variacs with mantles for the last 27 years and having used them as such
in university …
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@squig I don’t know if you have seen this topic. It covers a lot of different mantle control methods.
Maybe you could have a look and comment on the control i found.
I agree with you that a heating element can be controlled by a variac so long as it can provide enough current.
@spdking ( i’m not trying to cause an argument or anything, I don’t have a lot of money so have to be a cheapskate lol )
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that is a uk and australian model.
I am not sure where you are my friend.
dont stress about spdking he posts I suck cock for drugs so as I will not insult him I shall call him
accountable for his statements when it comes to science and tech.
so 220V is its limit so it will give you the total of your volts from the power point though not
good for 110v systems.
if your using a 220/240v system you wish it to go to 260v
if your using 110v I think its about 130 or 140v though as I am using 240v system I am not sure.
most autotransformers (variac is actually a trade name made in the states that stuck for other
products) go to 120% which is what you want but some do not hence me mentioning the over volt
or step up you need.
so look for one that goes to 120% over your voltage.
also what wattage is your mantle.
as for reduced current don’t stress when you turn it off you have the ultimate reduced current 
if its just a resistance element there is nothing other than too much power or reactive environments
like acids etc that will kill it (of course work over time does it too but all things die in time)
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just read your in the uk in another thread so you want one that goes to 260v
simple
light dimmers will never do this as they dont want to burn the lights out.
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I’m waiting for David to send my SPD kit so i have plenty of time for either a variac or some sort of 3rd party digital control as outlined in the other topic.
( I’m not stressed about SPDking, I just want to remain neutral hahah ) 
edit : yes i’m welsh but now live in barcelona
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my mum is from york shire.
you got to lay down some of the welsh lingo for me man I love it.
also light dimmers are normally triacs and as pid’s work turn power on and off.
so you might as well use a pid which will give you temp control for the same price.
this is the reason they are so cheap.
a solenoid/relay hooked to an ic chip requires minimal materials but to actually
convert electricity to another voltage requires a large coil of copper around a ferret core.
as always I am sorry to say we get what we pay for and yep variacs are expensive.
sorry that was not 100% right other things will do this too like resistors but the heat they generate
at such loads is a lot.
I would hate to try and run a heating element of a variable resistor the size of it would be huge.
that is why we use magnetics instead of resistance to convert ac like this
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Yes of course … peanuts in … peanuts out … lolo
I know i need to get a nice variac and a thermometer, it the most important thing after vacuum. The first thing i thought when i started seriously thinking about buying an SPD kit was this.
All my life i have hated electric cookers because they don’t hold a constant temperature like a gas cooker would due to one being a heating element turning on and off and the other being a constant stream of controllable heat.
After reading this site for days lolo I found the post i linked you to from @SkyHighLer. Logic would dictate that a constant variable power source connected directly to the heating element would be far superior to the on/off control of PID.
ALSO !!! A variac would be a far superior for of control for my electric cooker !!!
If the PID control could cycle within 0.5c it wouldnt be a problem but they over shoot by 20c sometimes and this is not acceptable for me trying to learn the art of distillation.
( all for the want of $60 to $120 )
As you said " you get what you pay for "
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fucking awesome.
you would be swimming in pussy down here talking like that.
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…IF they have not been trained on your process load…
switching the power on and off works really well to control the speed of my car (15kHz I believe).
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" If " is one of those words …
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It is.
have you run the auto-tune on your PID?
or read why that is important, or how it works?
Inanimate objects often appear broken if you haven’t asked them to do what you want. Or trained them to do it correctly. is it really their fault?
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yep so the question and as I have not done it I will not attempt and answer is
how ?
linked up thread… post three.
here is for the AI
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will check thanx
That made my split tea across the room with laughter.
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