This is a heavy duty 30 amp PWM i built and installed in my current HHO System. It has a built in cooling fan to keep the PWM cool and an led that varies with output.
Pulse width modulators are used to control the speed or duty cycle of items such as fans, light intensity, motors, solenoids among other things.
This particular PWM is capable of handling very large loads up to 30 amps. This is one of many reasons they are used in controlling heat and amperage runaway in HHO Systems. Without one HHO Systems simply won't work. As temps increase so does amp draw, until the unit overheats or melts.
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