Papa, nsa and max said it all.Why is that?
Papa, nsa and max said it all.Why is that?
I have some 2½ HP DC motors from treadmills that run thru all their speeds with power from a non-linear supply. I believe that all it is is 120V rectified to DC, then fed to the motor with a PWM signal using a bank of switching transistors.If you ever decide to work with DC motors, linear is the only one that is recommended for them.
There might not be any right or wrong - different manufacturers use whatever control topology they feel most confident with.I have some 2½ HP DC motors from treadmills that run thru all their speeds with power from a non-linear supply. I believe that all it is is 120V rectified to DC, then fed to the motor with a PWM signal using a bank of switching transistors.
But I could be wrong!
I've had lots of headaches with TCR power supplies being replaced with fancy SMPS units of the same power. Without very careful extra emi filtering and shielding they tend to shutdown at the first sign of system instability instead on blasting through high power transients like the old SCR units did.There might not be any right or wrong - different manufacturers use whatever control topology they feel most confident with.
Triac phase control was the standard - but its radio noisy.
There are two basic types of T.M. controllers, one is a simple SCR bridge version, the other Mosfet PWM, in both cases the T.M. supply is connected directly across the line, i.e. no SMPS, transformer, or dedicated supply.I have some 2½ HP DC motors from treadmills that run thru all their speeds with power from a non-linear supply. I believe that all it is is 120V rectified to DC, then fed to the motor with a PWM signal using a bank of switching transistors.
I haven't looked too closely at the controller yet - it was a curb find. The motor is a popular brand, 2½ HPish output (don't remember the exact HP or brand). I plan on using the motor and controller to power a 14" wood bandsaw (also a curb find) to convert it into a metal bandsaw.There are two basic types of T.M. controllers, one is a simple SCR bridge version, the other Mosfet PWM, in both cases the T.M. supply is connected directly across the line, i.e. no SMPS, transformer, or dedicated supply.
Max.
Don't open another thread -you are possibly on the threshold of getting what you are looking for. If you were to start a new thread on the same subject it would be merged with this one anyway.well, i have the electronics lab 0-30v 3A which never faild me so far, can u guys at least help me make it so it does at least 8A ? or should i open another threaad ?
anything, the one that gives me problems are some power leds that draw 15A@12v(PWM is a no go because of flickering on video), and then there is my induction heater that i have to connect to different transformers every time i want a bit more power and it's annoying.May I ask, what kind of circuits do you work on?
Yes.So, can this schematic be modified to get a few more amps ???View attachment 175721
If you understand the schematic -- I suppose. Do you really want to bite off a chunk this big?anything, the one that gives me problems are some power leds that draw 15A@12v(PWM is a no go because of flickering on video), and then there is my induction heater that i have to connect to different transformers every time i want a bit more power and it's annoying.
So, can this schematic be modified to get a few more amps ???View attachment 175721
I agree, it is a bit complex for a starter project. But *nothing* like the magnetics of a 1 kW switcher. If you don't get this:If you understand the schematic -- I suppose. Do you really want to bite off a chunk this big?