Silvio
Well-known member
@badboy_6120
From what I can see is that the current trafo is not producing enough current and hence not coupling enough magnetic field to the core. Due to this when putting the load resistor all the voltage produced in the secondary is dropping a lot. Well if you found a way with what you did then leave it like it is as long as its working.
One other problem that I faced in my smps is that it was hard to start and without a small inductor in the output (1.5uH) it will trip due to it seeing a dead short when charging the secondary caps. I have 4000uF on each rail. In my version I am using ETD49 and now I added feedback and is regulated to 60v-0-60v. It can peak up to 1200 watts and can run at 900 watts continuous all day.
You did not say what is the peak output voltage (no load) you have on your smps. What is the output voltage at 1500 watts?
Be careful if you are using halogen bulbs or heater elements as these tend to draw a lot of current during warm up and a 400 watt halogen can easily draw more than 10-15 from a cold start for a second or so. You will find that when starting on load it may work ok due to the soft start but if you had to load it while the smps is running then it might trip your overload protection.
You can take a look at the load test on my video. Here I was using the first bobbin wound for 90-0-90volts peak and the maximum load given here is around 1100 watts not regulated. Now I changed it and wound it for 75v peak without feedback. Adding feedback brings the need for an output inductor which in my case I used a common mode choke with a double 15uH and regulation to 60v,
The video can be found on this link https://www.youtube.com/watch?v=18l-plvqkdU
regards Silvio
From what I can see is that the current trafo is not producing enough current and hence not coupling enough magnetic field to the core. Due to this when putting the load resistor all the voltage produced in the secondary is dropping a lot. Well if you found a way with what you did then leave it like it is as long as its working.
One other problem that I faced in my smps is that it was hard to start and without a small inductor in the output (1.5uH) it will trip due to it seeing a dead short when charging the secondary caps. I have 4000uF on each rail. In my version I am using ETD49 and now I added feedback and is regulated to 60v-0-60v. It can peak up to 1200 watts and can run at 900 watts continuous all day.
You did not say what is the peak output voltage (no load) you have on your smps. What is the output voltage at 1500 watts?
Be careful if you are using halogen bulbs or heater elements as these tend to draw a lot of current during warm up and a 400 watt halogen can easily draw more than 10-15 from a cold start for a second or so. You will find that when starting on load it may work ok due to the soft start but if you had to load it while the smps is running then it might trip your overload protection.
You can take a look at the load test on my video. Here I was using the first bobbin wound for 90-0-90volts peak and the maximum load given here is around 1100 watts not regulated. Now I changed it and wound it for 75v peak without feedback. Adding feedback brings the need for an output inductor which in my case I used a common mode choke with a double 15uH and regulation to 60v,
The video can be found on this link https://www.youtube.com/watch?v=18l-plvqkdU
regards Silvio