Compact Switching Power SupplyMS2 series


Output Current 12.5 A, 300 W


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Input conditions

Input voltage

85 to 264 VAC, 110 to 370 VDC*1


47 to 63 Hz, DC*1


Input current (100/200 VAC)

3.9/1.8A or less

Efficiency (100/200 VAC)

82, 85% typ. (at 100% load)

Leakage current (100/200 VAC)

0.4, 0.75 mA or less (at 100% load)

Rush current (100/200 VAC)

18/36A or less

Output characteristics

Rated voltage


Variable voltage range

±5% (with V.ADJ)

Rated current


Ripple/noise voltage

180mV (p-p) or less

Input fluctuation

0.4% or less

Load fluctuation

1.5% or less

Temperature fluctuation

0.02%/°C or less

Startup time

500 ms or less (when the ambient usage temperature is between 0 and +55°C 32 and 131°F with rated I/O conditions)

Output holding time

20 ms or more (when the ambient usage temperature is +25°C 77°F and with rated I/O conditions)


Overcurrent protection

Constant current drop method, automatic recovery, 15.6 A or more

Overvoltage protection

Activates at 26.4 V or more, voltage interruption method, recovers when input is applied again*2


Display power

3-digit 7-segment LED (character height: 10 mm 0.39")

Power off memory time

Approx. 10 years (at +20°C 68°F)

Display resolution

0.1A/0.4V /1%

Applicable standards

Safety standards

UL: UL508, UL60950-1; C-UL: CSA C22.2 number 14-M95, CSA C22.2 number 60950-1-03; EN: EN60950-1, EN50178; IEC: IEC60950-1

EMC standard

FCC Part 15 B Class A, EN55011 Class A, EN61000-6-2

Limits for harmonic current emissions



Parallel operation

Possible (requires OP-42207)*4

Series operation

Possible (requires external diode)*4

Cooling method

Natural air cooling

Environmental resistance

Withstand voltage

3.0 kVAC, 50/60 Hz, 1 min (across input and output terminals)
2.0 kVAC, 50/60 Hz, 1min (across input terminals and PE terminal)
500 VAC, 50/60 Hz, 1min (across output terminals and PE terminal)

Insulation resistance

100 MΩ or more at 500 VDC
(between input and output, between input and FG, and between output and FG)


Ambient temperature

-10 to +55 °C 14 to 131 °F (No freezing) (see the derating characteristics)

Relative humidity

25 to 85 % RH (No condensation)

Environmental resistance

Ambient temperature for storage

-20 to +70 °C -4 to 158 °F (No freezing)


10 to 57 Hz, Double amplitude 0.3 mm 0.01", 57 to 500 Hz, 19.6 m/s2 (2 G), cycle: 5.5 minutes, 2 hours in each of the X, Y, and Z directions

Shock resistance

Peak acceleration: 300 m/s2, 2 times in each of the X, Y, and Z directions


Approx. 1,540 g

*1 The rated input voltage and rated frequency when applying for safety standards are 100 to 240 VAC, 50/60 Hz.
*2 To return, turn OFF the input power supply and after leaving it off for 1 minute or more, plug in the input power supply again. The E/F Series is a Zener diode clamp type. It will not restart after the protection circuit operation.
*3 For the MS2-H100, this is applicable only when the load ratio is 70% or less.
*4 The applicable standards do not apply for parallel and serial operations.

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