On Thursday, 9 November 2017 16:01:00 UTC, Matthias Czech wrote:
Am 09.11.2017 um 16:12 schrieb whisky-dave:


Yes why is a 2KW heater only drawing 700W when fully on, if it was up to temperatury I'd expect it to disconneced with a bimetalic strip or something more advanced and would be 0W not 700W.

I would expect that too.

The radiator has 2 switches. Call them A and B. Eeach switch has two
positions. Call them 'on' and 'off'.

So 4 combinations:

C1: SW A 'off' SW B 'off' 0
C2: SW A 'off' SW B 'on' 697W
C3: SW A 'on' SW B 'off' 1040W
C$: SW A 'on' SW B 'on' 1705W


Voltage 211, it does drop more than 1 volt with just one heater switching off and on. (with 5 on the same circuit we get down to 202V)

with thermostate at highest i.e always on. LEDs always on both switches.
When the thermostate is manually turned down from maxium I hear a click and the meter drops tom 0W as expected.

What I didn;t expect was that leaving the heater on for a couple of hours at full also resulted in a click and the power drops to ~700W rather than 0w
like I'd expect of a cut out. At this 700 both LEDs remain on, indicating to me that 1700W would be disapated rather than the 700W measured.



What are the readings of your 'old maplin power meter' for each of the 4
combinations?