MFJ MFJ-4230MV User Manual

MFJ-4230MV

30 Amp Switching Power Supply

User Manual

Specifications and Features:

4 to 16 VDC adjustable output, detent at 13.8VDC
30 Amps Surge (up to 5 minutes), 25 Amps Continuous
Light weight, only 3.4 lbs/1.35kg
Compact, only 5” x 2 ½” x 6” (W x H x D)
0 to 16V and 0 to 32 A selectable backlit meter
Five-Way binding post for high current radios
Over Voltage protection
Over Current protection with “FAULT” LED
QUIET Internal Cooling Fan with ”FAN” LED
Super Regulation, works with AC input from 85 to 135 VAC (115VAC model) or from 170 to 260

VAC (230VAC model), 47-63Hz

Ripple and Noise <100mV
AC Line Fuse( 6.3 Amps)

INSTALLATION:

Before plugging in the MFJ-4230MV in an AC outlet make sure that it is the proper input voltage of the
power supply. The MFJ-4230MV is factory set for 115V.
Place the MFJ4230MV in a place that does not block the cooling vents on the bottom, sides or back.
The load is connected to the 5-way binding posts on the back:
The RED binding post on the TOP is POSITIVE (+) terminal.
The BLACK binding post on the BOTTOM is the NEGATIVE (-) terminal.

OPERATION:

The MFJ-4230 Connect the output and turn the power switch to the ’ON’ Position.
Adjust the voltage to the required voltage. The detent on the voltage control is set to 13.8VDC. Be careful
not to exceed the voltage rating of the equipment connected to the power supply.
Before you turn the power supply off, turn the radio off as described in the user documentation for the
radio. Turn the power supply off by pressing the power switch to the ’OFF’ Position

PROTECTION:

The cooling fan on the MFJ-4230MV will operate when the unit is turned ON. The speed of the fan varies
depending on the DC control settings and the internal temperature. When power supply has been run for
a long period especially at higher currents we suggest before turning off the power supply you run the
power supply for a short period of time without any load to allow the cooling fan to reduce the
temperature.
The MFJ-4230MV will automatically shut off if over 30 amps of current is drawn from the outputs. To
reset, turn the unit OFF and wait 20 seconds, then turn the unit back on.
The MFJ-4230MV has a 6.3 amp AC input fuse at the front inside of the unit near the power switch. To
replace the fuse:

1. Turn off the unit, unplug and let sit for 15 minutes to allow the high voltage capacitors to
discharge.

2. Open the case.

3. Remove the old fuse.

4. Put in a new fuse of the same type size and current rating.

5. Close the case and connect back up.

Changing the input voltage from 115VAC to 220VAC is accomplished by the selector switch on the
rear of the unit. Just select the input voltage you will be using.

Do not open the power supply while operating or plugged in. There are high voltages present that can be
lethal.