A simple question came into my mind: reef angel PWM level is 10v. Is it possible to drive these pumps with 5v pwm level?

I'm sure it is. It may require a mod to the cable.

Roberto can chime in on that.

Are you trying to slow the pump down, buy reducing the voltage to it?

Yes. You need a modified cable. The jaebo's are actually controlled by 0-5V Analog. There is a filter on the jaebo cable that converts it to analog and also drops the voltage down. At least this is my understanding...

Oh, ok! I see there is a jumper at the cabe which enables a voltage divider working at 50%, so I just have to close the jumper to make PWM level work at 50%?

You have four inputs and three outputs. The inputs are 24 VCD, Ground DC (these both come from the power supply) and data 10 VDC and data ground. The data ground and power supply ground are joined on the board. The three outputs are data or control, 24 VDC and ground. Not sure where you're seeing a jumper. The data 10 VDC goes through a voltage divider to make it 5 VDC and a capacitor to smooth the PWM to analog.

Fat

Fatman, you are perfectly right. I thought the JP1 connector from the schematic posted by Sacohen was a jumper. Too fast analysis by myself. Thank you for your explanation. It got perfectly clear. Thank you!!

Jorge Ramalho wrote:Fatman, you are perfectly right. I thought the JP1 connector from the schematic posted by Sacohen was a jumper. Too fast analysis by myself. Thank you for your explanation. It got perfectly clear. Thank you!!

Not bad for a Fatman.