Harshana
16-01-2013, 04:34 AM
Hi all,
I bought a Whirlpool Protton 3door refrigerator (FP313 ELT) last May. I was replacing a 20yr old Sisil refrigerator still in working condition, but it was old. New fridge controller got fried in less than a week, it was replaced free as it was under warranty. Last November also the controller got fried. This too it was replaced after calling many times to the local agent. Weeks after it got fried again, clearly I should be having lot of electrical spikes. However, none of my other equipments TV, DVD player, washing machine, computer etc are not effected, but only the fridge burns. So I figured its bad supply and bad controller design.
When I closely looked at my controller cct, I realized they have simply used a cheap RC circuit to drop 240V to 5v and using it to run the PIC 16Fxxx uController. Obviously, any electrical spike large enough to jump through the capacitor will hit the ucontroller with high voltage.
Ignoring the offer by the agent to return the refrigerator and go for a new model, I decided to build my own controller.
So I made a simple cct with a uController that reads the temperature from the two thermistors and switch on and off the compressor. With little bit of experimenting, I realize that I should leave the compressor off at least for 5 minutes between each run.. If not, there's risk of compressor being switched off from the protection switch at the compressor.
I think when the compressor runs for sometime, then there's pressure built up at the output. When stopped, we need to keep it for sometime till the pressure drops. If I start the compressor too soon, It will not be able to start-up and it gets stuck, so the protection switch goes off.
So far, I have better power consumption than with the original controller (roughly 1kWh / day, freezer @ -12C).
My question is : Does the min off time depends on the amount of time the compressor runs. Eg. Running the compressor for 5minutes should have 5minute off time and if I run it for 2minutes, will the min off time drops ?
I have attached a wiring diagram with little bit of additional information.
Thanks,
Harshana
PS: To the admin. Please make docx also a valid file format.
I bought a Whirlpool Protton 3door refrigerator (FP313 ELT) last May. I was replacing a 20yr old Sisil refrigerator still in working condition, but it was old. New fridge controller got fried in less than a week, it was replaced free as it was under warranty. Last November also the controller got fried. This too it was replaced after calling many times to the local agent. Weeks after it got fried again, clearly I should be having lot of electrical spikes. However, none of my other equipments TV, DVD player, washing machine, computer etc are not effected, but only the fridge burns. So I figured its bad supply and bad controller design.
When I closely looked at my controller cct, I realized they have simply used a cheap RC circuit to drop 240V to 5v and using it to run the PIC 16Fxxx uController. Obviously, any electrical spike large enough to jump through the capacitor will hit the ucontroller with high voltage.
Ignoring the offer by the agent to return the refrigerator and go for a new model, I decided to build my own controller.
So I made a simple cct with a uController that reads the temperature from the two thermistors and switch on and off the compressor. With little bit of experimenting, I realize that I should leave the compressor off at least for 5 minutes between each run.. If not, there's risk of compressor being switched off from the protection switch at the compressor.
I think when the compressor runs for sometime, then there's pressure built up at the output. When stopped, we need to keep it for sometime till the pressure drops. If I start the compressor too soon, It will not be able to start-up and it gets stuck, so the protection switch goes off.
So far, I have better power consumption than with the original controller (roughly 1kWh / day, freezer @ -12C).
My question is : Does the min off time depends on the amount of time the compressor runs. Eg. Running the compressor for 5minutes should have 5minute off time and if I run it for 2minutes, will the min off time drops ?
I have attached a wiring diagram with little bit of additional information.
Thanks,
Harshana
PS: To the admin. Please make docx also a valid file format.