Instruction Manual
Thank you for purchasing the MSE Switching Power Supply . The MS-280Ais designed to
supply up to 28 amps maximum current or 25 amps continuous current at 13.8 Vdc.
INSTALLATION:
Before plugging in the MS-280A in an AC outlet make sure that the proper input voltage is selected
on the rear of the unit. Select 115 for 100/110/120AC operation or 230 for 200/220/240 AC
operation. MS-280A is factory set for 230V.
The loads can be connected to either the 5-way binding posts or to the cigarette lighter socket. Note
that any devices that require more than 7 amps must use the 5-Way binding post output. The
cigarette lighter socket output has a maximum output of 7 amps.
OPERATION:
DC Adjustment: The DC adjustment control on the front panel is used to set the DC output voltage
of the MS-280A from 9 volts to 15 volts DC. For most HF and VHF radios, set the output at
13.8Vdc.
FAN: The cooling fan on the MS-280A will operate when the unit is turned ON. The speed of the
fan varies depending on the temperature control circuit the speed of the fan, the brighten the yellow
LED is the faster the fan is working.
Meter Indicators : The current meter on the MS-280A indicates the total current being drawn by
the accessories connected to the power supply. The voltage meter on the MS-280A indicates the
voltage set for the 5-way binding pose output, and the cigarette socket output .Both meters will be
lit when the unit is turned ON. Upon the DC voltage is adjusting. It won’t affect the brightness of
the lamps inside the volt/amp meters.
PROTECTION:
The MS-280A will automatically shut off if over 30 amps of current is drawn from its outputs. To
reset, turn the unit OFF and wait 20 seconds, then turn the unit back on.
The MS-280A has a 220volt/5amp fuse in the power cord connection on the back of the unit. The
MS-280A has two slots for these fuses. The slot closest to the unit locks the fuse in place and then
becomes part of the circuit. The slot at the rear of the tray is a place to store a spare fuse for
emergency cases.
