2PAC Mafia
Member
Hello,
I´m checking a treadmill 180VDC motor controller. The customer told me at start moment he measured 300V so he sent me the MCB to be checked. I´ve been checking the PCB and I can start and stop it from theorical console signals, it works. Then there are signals for UP and DOWN rpm which goes to 2 optocouplers. When a give pulse at optocoupler for UP it switches motor MOSFET and create this signal:
http://www.restoretronic.com/descargas/cintas/1.jpg
http://www.restoretronic.com/descargas/cintas/2.jpg
so as you can see the circuit works from signal from console to last step at Mosfet switching. What I don´t know is the logic behind the console control because in theory when treadmill starts it should do it giving to motor around 30Vdc but the customer measured 300Vdc. If measure with scope the Mosfet output I see as lower point 180Vdc so means maximum motor voltage and if I measure with multimeter it shows 300Vdc. I guess this is because of frequency switching.
I would like to know how can I change speed signal demand input to change PWM input to Mosfet. I see console sends 5Vdc to anode optocoupler diode and catode goes to console also. The serial yellow LED flashes usually so I think console send some kind of frequency pulse.
When I simulate signal I only can get maximum voltage output or 0V output...
I´m checking a treadmill 180VDC motor controller. The customer told me at start moment he measured 300V so he sent me the MCB to be checked. I´ve been checking the PCB and I can start and stop it from theorical console signals, it works. Then there are signals for UP and DOWN rpm which goes to 2 optocouplers. When a give pulse at optocoupler for UP it switches motor MOSFET and create this signal:
http://www.restoretronic.com/descargas/cintas/1.jpg
http://www.restoretronic.com/descargas/cintas/2.jpg
so as you can see the circuit works from signal from console to last step at Mosfet switching. What I don´t know is the logic behind the console control because in theory when treadmill starts it should do it giving to motor around 30Vdc but the customer measured 300Vdc. If measure with scope the Mosfet output I see as lower point 180Vdc so means maximum motor voltage and if I measure with multimeter it shows 300Vdc. I guess this is because of frequency switching.
I would like to know how can I change speed signal demand input to change PWM input to Mosfet. I see console sends 5Vdc to anode optocoupler diode and catode goes to console also. The serial yellow LED flashes usually so I think console send some kind of frequency pulse.
When I simulate signal I only can get maximum voltage output or 0V output...