Berd Air External MOSFET driver with Volt/Current Meter

If you need to install an external MOSFET driver to run the Berd Air pumps, this is a housing to hold the driver and a panel to monitor the current/voltages on the pumps. The current/volt meter provides a quick way to assess the load on the motor. If the motor is using too much current, you will be able to detect a problem before it becomes serious. The panel keeps everything tidy and the terminals in the back provides connection to the power and the load.

Even though it is easier to use the internal MOSFET on most control boards, the external MOSFETs can handle more current and is less likely to damage the control board. The BIQU MOSFET board has protection circuits and the inputs are not sensitive to polarity since it has a full bridge rectifier on the input side. You will not have to add a flyback diode on the motor (although its suggested to add one to the DC motor in case the motor is used on an another driver which does not have the protection.)

It is easy to wire the circuit. The power goes to the terminal block. From the terminal block, it goes to the input of the BIQU MOSFET driver. The output of the driver goes to the panel meter and also to the terminal block for the DC motor. You can make an extension cable for the PWM input to the BIQU or just wire the cable directly through the open slot in the back.

Note: Do not use other types of volt/current meters that has a LED display. The voltage/current connections are tied on the negative terminal. The MOSFET driver (HA210N06) is a N-channel mosfet, so the ground is circuit side that is being switched. If you use the LED display, the MOSFET would be bypassed since the return ground would go through the common ground connection on the display. The LCD display used below does not have that issue since the ground and positive are not tied between the volt input and the current shunt.

Part list:

(search in eBay or AliExpress)
MOSFET Board: Search for "Biqu mosfet"
Panel Meter: Search for "volt current energy meter lcd"
Terminal Block: Search for "TB1504" (Model is Weidu TB1504, but any block with 44mm screw spacing will work)

Motor Heatsinks: Search for "540 motor heatsink"

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