[geck0uk]

The fridge/compressor has been running OK for the past one month.
A SmartMeter has been installed to the flat recently which allowed me to monitor/measure the load characteristics. (The display updates every 10 seconds).
The result (image has a link to a full sized version via Dropbox):

[IMG2=JSON]{“data-align”:”center”,”data-linktype”:”1″,”data-linkurl”:”https://www.dropbox.com/s/0601rxwh1x40gr8/Fridge-Compressor_Starting_graph.png?raw=1″,”data-size”:”full”,”height”:”288″,”title”:”Fridge-Compressor_Starting_graph.png”,”width”:”598″,”src”:”https://www.dropbox.com/s/0601rxwh1x40gr8/Fridge-Compressor_Starting_graph.png?raw=1″}[/IMG2]

The way I created the chart: I video-recorded the SmartMeter with all other electronic devices off. For all kitchen appliances there’s a fused switchboard, close to the fridge. The switching sound is swift and also loud enough to be audible on the recording. I tried to time the switch-on moments to spread the measurement points within the 10 seconds period (with not a great success).
(I could have measured the voltage on the PTC with a multimeter, however to do so the fridge needed to be “dismounted” from the cabinet; Having all electronic devices off also allowed me to check the main fuse-box of the flat along with checking the power consumptions of each electrical appliance.)
The video files are available under the same link as the sound recordings (#1st post): Dropbox link

For me the main news was that the time for the PTC to “disconnect” the start-winding of the compressor takes up to 50..60 seconds.

Furthermore I’ve learned:

• with the in-rush current of a starting, 120W compressor the usage can result in a peak ~930W (3.875 A) and it can last up to 3+ seconds
• in case the PTC is off (e.g. remained hot after a quick switching back on event) the power consumption of the blocked compressor is ~795W
  The time for the PTC to cool off, in my case, took about 3..4 minutes. From it I conclude that the compressor must withstand the heating power of about 800 watts for at least this period of time (the heating motor lengthens the time for the PTC to cool down) without any serious damage.

I hope it’ll be helpful for others.

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