The question can easily be resolved with a simple measurement by dunkel. What is the resistance between the +ve terminal of C13 and B-, and what is the resistance between the +ve terminal of C13 and the emitter of T7?
The question can easily be resolved with a simple measurement by dunkel. What is the resistance between the +ve terminal of C13 and B-, and what is the resistance between the +ve terminal of C13 and the emitter of T7?
So you don't want to verify my schematic by the board from which is was drawn from?
The windings on the transformer appear to have been drawn incorrectly. That's the source of the error.
AISI pins 3 & 4 are the winding that drives the middle transistor whereas 1 & 2 drives the outside one. So the winding that is drawn between pins 1 & 4 should actually run between pins 3 & 4.
In any case it's impossible to determine the actual layout simply by visual inspection. That's why a measurement is necessary.
How did you assign which one to be pin 1 in my drawing so I can see what you are saying?
There are 5 pins on the left side, 3 pins on the right side.
I think I see where my mistake is, one of the Gate drive winding should not be connected to GND, I have one end of both Gate drive windings connected to GND so that is wrong. I should have caught that if I draw up the schematic like Keeney suggested in the beginning, sorry.
The topology is similar to this: http://danyk.cz/s_atx01h.png
How did you assign which one to be pin 1 in my drawing so I can see what you are saying?
There are 5 pins on the left side, 3 pins on the right side.
I think I see where my mistake is, one of the Gate drive winding should not be connected to GND, I have one end of both Gate drive windings connected to GND so that is wrong. I should have caught that if I draw up the schematic like Keeney suggested in the beginning, sorry.
The topology is similar to this: http://danyk.cz/s_atx01h.png
Its pinout is BCE (left to right). The MJE13007 is a higher current, higher wattage version of the MJE13005G, so ISTM that it should be a good choice, provided that the pinout is correct. Just make sure to use heatsink insulation if necessary. I also notice that neither transistor has a CE diode, so that explains the one on the PCB.
Hello, sorry for the delay i haven't checked my transistor i will do this weekend so i hope i can find a similar one.
Hello, sorry for the delay i haven't checked my transistor i will do this weekend so i hope i can find a similar one.
Thanks
Just want to let you know that the schematic is off. I am not sure what is off but BudM's virtual component layout was off and fzabkar caught it. I could not get anyone to correct the schematic.
Just want to let you know that the schematic is off. I am not sure what is off but BudM's virtual component layout was off and fzabkar caught it. I could not get anyone to correct the schematic.
dunkel I wonder if you could verify the schematic by ohming it out to find where it is in error?
Hello,
I've bought Thomson's wine fridge Millesime 18 but I'm not convinced about the performance. As the room temperature is about 23°C, the fridge can't go below 16°C. So I'd like to optimize it and probably change some elements.
I've discovered the power board is HYS60-12-KD. It's very similar to the one describe on this post, but still some variants as it can only drive one peltier module (IC3 is not present).
My idea is to change the peltier module to a more powerful one. But I need to know how much power the board can deliver not to buy an oversized module.
I read the exchanges above and spend few hours to design the power part on KiCad (opensource). So I thank you for the schematics you posted as they were really helpful.
You'll find the design attached. Please let me know if something is wrong.
Thanks for your updated schematic. I can now see the error in the other one were the transformer was attached. I was a technician perhaps one of the engineers would help you in getting a Peltier that can drive these cooler under 60F. Seems that is the best they can achieve. You need to be careful as to the parameters on the Peltiers. The ones from China will not draw anymore than 2.7 Amps at 12 volts before they burn up. One person got some from an American Supplier and it would draw the 6.5 Amps but I think it did eventually burn up. I had a refrigerator that had 2 Peltiers but I bought the Chinese ones. The unit was rated as 130 Watts figuring that is RMS the Average DC would be a little less perhaps 120 Watts. To drive that one would need 10 amps at 12 volts. Each Peltier would need to draw 5 amps. When some people list the currents that Peltiers can handle it is for a temporary time which may not be able to overcome the ambient. My refrigerator was rated at 70 F ambient and said the maximum it would get down to was 37 F. The American Peltiers cost a minimum of $22 each. The power supply seems to me to be large enough to drive the 10 amps of current at 12 volts. It is the Peltiers that can not handle this current for any amount of time. One could calculate on much power one would need to drop the temperature inside an given insulated space over a given time. I would say it would take a minimum of 8 hours to significantly drop the temp. Also, know that when these Peltiers are putting out a lot of heat they are working very hard doing what they are suppose to do. That is take heat from an inside space and deliver it to and outside space and remember every time one opens the door that these Peltiers will have to overcome that heat. Peltiers are very inefficient and are use usually used to create electricity in areas that do not have power buy burning wood/etc. on one side creating a temperature difference which than generates electricity. Also, If you reverse the current you could also have a heater.
To test out the Peltier devices one would disconnect them from the power board and connect them to and external good power supply. The Peltiers would remain assembled in the unit. The fans should also be disconnected from the power board and connected to external power so they would turn. The current and voltage should be monitored to make sure and over current or over/under voltage does not happen according to specifications of the Peltiers. A power supply where one can adjust both current and voltage is preferable, but not necessary. A linear supply is also preferable. If the Peltiers are good the unit will cool and there should be heat coming from the heat sinks. As the cooling process continues the heat sinks will put out less heat. A noticeable cooling will happen in 8 hours.
Hello,
I've bought Thomson's wine fridge Millesime 18 but I'm not convinced about the performance. As the room temperature is about 23°C, the fridge can't go below 16°C. So I'd like to optimize it and probably change some elements.
I've discovered the power board is HYS60-12-KD. It's very similar to the one describe on this post, but still some variants as it can only drive one peltier module (IC3 is not present).
My idea is to change the peltier module to a more powerful one. But I need to know how much power the board can deliver not to buy an oversized module.
I read the exchanges above and spend few hours to design the power part on KiCad (opensource). So I thank you for the schematics you posted as they were really helpful.
You'll find the design attached. Please let me know if something is wrong.
Trillien
Did you have any luck with this? The units is rated at rate at either input wattage or output wattage these are the limits of the power supply.
Hi,
Its 2017 and I am trying to fix one of these supplies from my Haer wine fridge.
The problem is at startup. Watching the VDD line, it cycles for a little while and then gives up. If I remove the Peliter load, it will power up fine to 12V, the fans and LED works..If I then hook up the Peltier, it keeps working fine. I can adjust the temp and everything.
This is the third one of this supply that has gone bad, I am tired of buying new ones. On one of the other ones, I pulled, tested and replaced all the LV caps.
The worst ESR was 22ohms but most were low and some were lower than the new ones! I don't think it is caps. That one is not fixed and actually runs the fans and LED but not the Peltier even after the disconnect trick.
ALL had a bad C8 Vdd supply cap. ESR was about 33ohms!
Having a bad Vdd caused two of the supplies to also blow T5 small NPN transistor. I replaced one T5 with a common 2n3904 I had, seems to work fine.
I need to get another C8 for the other supply.
C8 seems to be under the most stress. Is there a really good replacement that could fix the un-reliability of this supply?
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