If you set an electric oven to say 100 degree C on the control - what
sort of swing would you expect between max and min temps in oven as
thermostat switched in and out.  What sort of temperature would you
expect it to switch at - as I assume there is a "hysterisis"  type
lag.


Are they typically plus or minus x%?

On Thu, 26 Jun 2008 17:28:44 +0100, andrew wrote:

> If you set an electric oven to say 100 degree C on the control - what
> sort of swing would you expect between max and min temps in oven as
> thermostat switched in and out.  What sort of temperature would you
> expect it to switch at - as I assume there is a "hysterisis"  type lag.
> 
> 
> Are they typically plus or minus x%?

You can easily measure this by moving the dial and listening for the 
click. IME on an electric oven the hysteresis could well be +/- 10C. 
The calibration might easily be 5-10 or even more out. For this reason 
you have to 'learn' your oven. 

Doubtless commercial duty kit is a lot better in both respects. 



-- 
Ed Sirett - Property maintainer and registered gas fitter.
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Ed Sirett wrote:

> You can easily measure this by moving the dial and listening for the 
> click.

That will establish the hysteresis band of the thermostat, but the 
temperature swing in the oven is likely to be larger.  When the 'stat 
contacts open (temperature rising) the heat stored in the hot element 
will cause the general oven temperature to continue rising for a while. 
  This overshoot will be greater if the oven is lightly loaded than if 
it is full.

-- 
Andy

In article ,
	Andy Wade  writes:
> Ed Sirett wrote:
> 
>> You can easily measure this by moving the dial and listening for the 
>> click.
> 
> That will establish the hysteresis band of the thermostat, but the 
> temperature swing in the oven is likely to be larger.  When the 'stat 
> contacts open (temperature rising) the heat stored in the hot element 
> will cause the general oven temperature to continue rising for a while. 
>   This overshoot will be greater if the oven is lightly loaded than if 
> it is full.

And the temperature variation of different parts of the oven
(even a fan oven) will be greater and more significant from
the cooking perspective. Comes back to learning your oven,
as Ed said.

-- 
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

"andrew"  wrote in message 
news:7kg7641v3om5epfcad93g0etp83h8ke2g3@4ax.com...
>
>
> If you set an electric oven to say 100 degree C on the control - what
> sort of swing would you expect between max and min temps in oven as
> thermostat switched in and out.  What sort of temperature would you
> expect it to switch at - as I assume there is a "hysterisis"  type
> lag.

I used a meter to test mine out of curiosity.
I set the  oven to 200C  it took about 10 mins to reach 200C,
The heater light came off and on somewhere  between ~197 & ~209
as measured on a thermocouple dangled roughly in the middle of the bottom
oven.

Cooker was a Zanuis/electrolux  electric fan assisted   one I brought from 
Argos
for about £550 a year ago.
The meter I'd say was about 2% accuracy .
I was quite suprised how close the numbers were, another thing I noticed was
how quickly the temepature fell once I opened the oven door.
It could take 3-5 mins or so for the temperature to stabilise.

whisky-dave wrote:
> "andrew"  wrote in message 
> news:7kg7641v3om5epfcad93g0etp83h8ke2g3@4ax.com...
>>
>> If you set an electric oven to say 100 degree C on the control - what
>> sort of swing would you expect between max and min temps in oven as
>> thermostat switched in and out.  What sort of temperature would you
>> expect it to switch at - as I assume there is a "hysterisis"  type
>> lag.
> 
> I used a meter to test mine out of curiosity.
> I set the  oven to 200C  it took about 10 mins to reach 200C,
> The heater light came off and on somewhere  between ~197 & ~209
> as measured on a thermocouple dangled roughly in the middle of the bottom
> oven.
> 
> Cooker was a Zanuis/electrolux  electric fan assisted   one I brought from 
> Argos
> for about £550 a year ago.
> The meter I'd say was about 2% accuracy .
> I was quite suprised how close the numbers were, another thing I noticed was
> how quickly the temepature fell once I opened the oven door.
> It could take 3-5 mins or so for the temperature to stabilise.
> 

I just used almond macaroons to test mine. The ones on the back of the 
tray were burning while those at the front were not quite done. Belling 
cooker - top oven. Dreadfully uneven - will use main oven next time.

But very nice... mmmmmmmmmmm

Recipe available.

-- 
Rod

Hypothyroidism is a seriously debilitating condition with an insidious 
onset.
Although common it frequently goes undiagnosed.
<www.thyromind.info> <www.thyroiduk.org> <www.altsupportthyroid.org>