Test of the minimum power measurable by different wattmeter sockets

[Christophe]

Lying ? Cons. in stop mode (off): 0.5 W https://www.electromenager-compare.com/ ... 2WFR-N.htm

Manufacturer Whirlpool? https://whirlpool-cdn.thron.com/static/ ... ZHXCSB.pdf

Congratulations you have just understood that Europe is a great scam…

[Petrus]

Here is the new data:
I also tested with a 75W bulb on a dimmer set to 50% which therefore cuts half of the sinusoid.

XAVAX:
Compact fluorescent: 19,1W
Condo LED: 5W
LED elec. : 4,5W
75W 50%: 47,2W
25VA transformer: 3,2W
100VA transformer: 9W

IDK:
Compact fluorescent: 18W 226V 0,13A cos.phi: 0,61
LED cap: 5W 227V 0,105A cos.phi: 0,21
LED elec. : 4W 227V 0,035A cos.phi : 1
75W 50%: 43W 227V 0,26A cos.phi: 0,73
25VA transformer: 3W 227V 0,04A cos.phi: 1
100VA transformer: 8,4W 228V 0,1A cos.phi: 0,37

Paget:
Compact fluorescent: 18W 223V 0,13A cos.phi: 0,63
LED cap: 5W 223V 0,1A cos.phi: 0,24
LED elec. : 4W 223V 0,04A cos.phi : 0,47
75W 50%: 43W 222V 0,26A cos.phi: 0,75
25VA transformer: 2W 223V 0,1A cos.phi: 0,24
100VA transformer: 8W 223V 0,1A cos.phi: 0,36

Voltcraft:
Compact fluorescent: 18,3W
Condo LED: 4,2W
LED elec. : 3,5W
75W 50%: 44,6W
25VA transformer: 2,4W
100VA transformer: 8,4W

Otax
Compact fluorescent: 18W
Condo LED: 0W
LED elec. : 0W
75W 50%: 43W
25VA transformer: 0W
100VA transformer: 7W

[izentrop]

Otax lacks sensitivity, I had noticed with mine. The others have relatively correct results.
What does the modified PM 230 give?

Congratulations you have just understood that Europe is a great scam…

You laugh , brands have no interest in not complying with standards.
Is it either a damage, a version not intended for Europe, a defect of the PM231?

[dede2002]

I will try with other measuring devices as soon as I can.
I compared the PM231 several times with other measuring devices, and with the manufacturer's indications (on the led bulbs the intensity is marked), it was always correct.

--------

Here is the new data:
I also tested with a 75W bulb on a dimmer set to 50% which therefore cuts half of the sinusoid.
...
IDK:
Compact fluorescent: 18W 226V 0,13A cos.phi: 0,61
LED cap: 5W 227V 0,105A cos.phi: 0,21
LED elec. : 4W 227V 0,035A cos.phi : 1
75W 50%: 43W 227V 0,26A cos.phi: 0,73
25VA transformer: 3W 227V 0,04A cos.phi: 1
100VA transformer: 8,4W 228V 0,1A cos.phi: 0,37

Paget:
Compact fluorescent: 18W 223V 0,13A cos.phi: 0,63
LED cap: 5W 223V 0,1A cos.phi: 0,24
LED elec. : 4W 223V 0,04A cos.phi : 0,47
75W 50%: 43W 222V 0,26A cos.phi: 0,75
25VA transformer: 2W 223V 0,1A cos.phi: 0,24
100VA transformer: 8W 223V 0,1A cos.phi: 0,36

...

Amazing these big differences in cos phi.
Most of the measurements displayed (for the elec led and the small transformer) do not correspond to the calculated values...?

[Petrus]

Otax lacks sensitivity, I had noticed with mine. The others have relatively correct results.
What does the modified PM 230 give?

Brennenstuhl PM230 modified:
Compact fluorescent: 20W 234V 0,092A cos.phi: 0,94
LED cap: 8,6W 233V 0,103A cos.phi: 0,48
LED elec. : 4,5W 233V 0,02A cos.phi : 0,97
75W 50%: 51,6W 233V 0,2092A cos.phi: 1
25VA transformer: 7,5W 233V 0,047A cos.phi: 0,70
100VA transformer: 14W 233V 0,104A cos.phi: 0,59

Mwais, not sure that the modification is a good idea, it is more sensitive but not very precise.

You laugh , brands have no interest in not complying with standards.

Yes, like eg. for diesel engine NOx emission standards

[izentrop]

Mwais, not sure that the modification is a good idea, it is more sensitive but not very precise.

Exaggeration on power and cos phi. Maybe go back to settings.
It is nevertheless interesting to be able to evaluate the low powers lower than 1 W.

The wifi box varies between 8 and 10 W.
The laptop of 2017: 9 - 10 W in operation and 0,4 W in standby
My TV is also 0.4 W measured in standby.

Oddly in resistive power or with capacitive component it does not know how to measure less than 1.2 W

[dede2002]

Hi tlm and happy new year

I measured the day before my washing machine with a new Chinese gadget.
it oscillates between 1.1 and 1.2 W, with 50mA

standby LL11.JPG (72.4 KiB) Viewed 669 times

veilleLL12.JPG (80.4 KiB) Viewed 669 times

I don't know if the LL has a defect, or if it cheats, or if the two measuring devices are wrong...?

Out of curiosity I tested the consumption of the two counters, by themselves (entering through the exit) and one through the other.

The sino measures itself at 0.00 while it consumes 0.4W with a fp of 100% according to the PM231.
The PM231 measures itself at exactly the same value as with the sino (0.3W with an fp of 6%...)

[izentrop]

I don't know if the LL has a defect, or if it cheats, or if the two measuring devices are wrong...?

1,2 W for 1,3 W, they are valid every 2 almost ready.
I did tests with a 2-channel oscilloscope. Even with visualization of the current/voltage phase shift, it is not at all easy to draw something concrete from switching power supplies.

Recent energy meters are doing quite well, even on low power, without breaking their heads with calculations.
I measured on LED lamps where the power indicated is respected, with a current signal that is nevertheless quite chaotic.

The advantage of your SDM009 is that it can measure both low and very high powers with its current loop.

[dede2002]

I made some measurements with both devices, sometimes they agree, sometimes not...
The pm231 seems more relevant, sometimes.
Here is an example with a led bulb marked 2.5W 25mA (calculated fp 43%)

led 2.5W.JPG (107.41 KiB) Viewed 584 times

pm231-led 2.5W.JPG (128.5 KiB) Viewed 584 times

In this case, the pm231 displays an fp of 95%...
Sino values ​​are closer to those shown.

[dede2002]

I found something weird in some recycled boxes.
I thought it was an ultrasonic mosquito repellent, but it's an "electricity saver", it's called "power factor saver", it makes sense from the packaging to lower the electricity bill :P

pfs graph.JPG (132.01 KiB) Viewed 583 times

pfs plaq.JPG (93.63 KiB) Viewed 583 times

Demonstration (with Chinese meter)

2.5W LED alone

led 2.5W.JPG (107.41 KiB) Viewed 583 times

2.5W LEDs with PFS

led 2.5W with pfs.JPG (120 KiB) Consulted 583 times

transformer alone:

transfo36912.JPG (125.14 KiB) Viewed 583 times

transformer with pfs

transfo-pfs.JPG (133.06 KiB) Viewed 583 times

Amazing isn't it? With a Chinese meter I want to believe that the electricity bill decreases

The pm231 is not fooled, it always indicates 0.5W and 140mA more!