Outback FM-60 diversion load using N-Channel MOSFET.mp4

Outback FM-60 driving 60V 60A N-Channel MOSFET from 12V Aux output set in Diversion SSR mode. PWM frequency is about 333 Hz. Load resistor is 2 Ohm 400W, providing 15A of load at 29.4V. It's important to wire the MOSFET to switch Negative wire, not Positive. The problem is that FM-60's Aux output is not ground isolated, which causes a short circuit between Aux Negative terminal and battery Positive every time MOSFET closes, which caused destruction of MOSFET because 20A fuse is not fast enough. There are 1/4W 500 Ohm resistors on both Aux terminals to reduce transistor gate voltage and current and to serve as fuses too now. And 3K - 5K resistor from MOSFET gate to ground. 440 mF 35V capacitors are there to smooth out ripple, but 0.5V ripple is still there. Would be nice if Outback provided option to increase PWM frequency to 4 - 16 Khz.

Category:

Science & Technology

Tags:

• diversion load
• fm-60
• outback
• solar panel
• off-grid