Vermes
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This power supply has three modes:
- Double – 2 channels 0-30V with current 0.002-5A
- Symmetrical – 1 channel 0-60V with current 0.004-5A
- Parallel – 1 channel 0-30V with current 0.002-10A
Each module has it's own measures, the middle measure is used for reading the symmetrical tension (to not have to add channels).
Power module:
These are the widely known and appreciated Electronics modules with some changes:
- power transistors changed to 3xTip35C with emitter resistors
- 10'000uF filtration changed to 20'000uF
- Diodes changed to rectifier bridges
- Resistors R7 changed from 10W ones to 20W
Power:
Firstly, it was a transformer on EI core, but it heavily heated and buzzed. It was changed to a toroid with 300VA power – unfortunately, the tension was too big – it damaged the operational amplifiers, therefore, rectifier diodes were planted on the power path in order to break the tension (for 2 channels two bridges) – a soft-start was added.
Measures:
The measures show: intensity, tension, set current and the mAh to the load.
The central measure is a ICL7107.
Additionally, the power supply was equipped in automatic adjusting of fans rotating speed.
Temperature:
At fool power, the temperature stabilizes it on 80 degrees on 100% of rotation speed of fans. Above that, a thermal safety switch was included.
Tests:
Why 2 channels?
For example if you want to repair a car central lock – one takes more than 3A.
This solution will help to build more useful devices on it inter alia a retro nixie clock, an amplifier on mosfets, spectrum analyzer.
Final information:
The power supply switches off when the temperature reaches 90 degrees.
The power supply is very tough – it traveled many times in public buses and it works very well (it has only some damage on the housing).
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