Heaters with "electronic" thermostat

I have seen a huge rise of oilfilled electric heaters with "electronic"
regulation in europe lately. My guess is that those regulators work just like
ordinary lightbulb dimmers, althought with higher power.
(assumed triac control with forward phase regulation)
Light dimmers will distort the powergrid some, but heaters are a lot more
powerfull and with rapidly increasing numbers they are likely to cause more
EMI etc.. Is there anything in the workings that will make them outlawed?
Will the powergrid in residential areas become a royal source of noise?
(and overheated motors, broken computers etc..)

 

[John Larkin]

On 16 Nov 2004 22:49:45 GMT,
pbdelete@spamnuke.ludd.luthdelete.se.invalid wrote:

I have seen a huge rise of oilfilled electric heaters with "electronic"
regulation in europe lately. My guess is that those regulators work just like
ordinary lightbulb dimmers, althought with higher power.
(assumed triac control with forward phase regulation)
Light dimmers will distort the powergrid some, but heaters are a lot more
powerfull and with rapidly increasing numbers they are likely to cause more
EMI etc.. Is there anything in the workings that will make them outlawed?
Will the powergrid in residential areas become a royal source of noise?
(and overheated motors, broken computers etc..)

Heaters often use zero-crossing cycle bursts, which aren't as noisy
and presumably have less nasty effects on the power grid as compared
to phase control. Could make the lights flicker, though.

I had a customer once who wanted to know the power factor of a
zero-crossing triac'd waveform. The concept is nearly meaningless.

John

 

[Fred Bloggs]

pbdelete@spamnuke.ludd.luthdelete.se.invalid wrote:

I have seen a huge rise of oilfilled electric heaters with "electronic"
regulation in europe lately. My guess is that those regulators work just like
ordinary lightbulb dimmers, althought with higher power.

Nah- ON/OFF control all the way- there is nothing proportional- and
"electronic" most likely refers to a thermistor temperature sensor with
setting comparator driving a high power miniaturized sealed relay which
throws line power onto the heating element. The whole purpose of the
*oil* is add a thermal mass for smoothing of the temperature response-
who in their right minds would then make the voltage drive proportional.

 

[Spehro Pefhany]

On Mon, 22 Nov 2004 14:50:43 GMT, the renowned Fred Bloggs
<nospam@nospam.com> wrote:

pbdelete@spamnuke.ludd.luthdelete.se.invalid wrote:
I have seen a huge rise of oilfilled electric heaters with "electronic"
regulation in europe lately. My guess is that those regulators work just like
ordinary lightbulb dimmers, althought with higher power.

Nah- ON/OFF control all the way- there is nothing proportional- and
"electronic" most likely refers to a thermistor temperature sensor with
setting comparator driving a high power miniaturized sealed relay which
throws line power onto the heating element. The whole purpose of the
*oil* is add a thermal mass for smoothing of the temperature response-
who in their right minds would then make the voltage drive proportional.

Time proportioning is pretty common in temperature control and adds
little to the cost. It has very little downside if the output device
can handle the number of operations.


Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
speff@interlog.com Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com