1 Function
1.1 Input Voltage Range
¡
If Input voltage value doesn’t fall within specifications, a unit may
not operate in accordance with specifications and/or fail.
1.2 Overcurrent Protection
¡
Overcurrent protection is built-in and comes into effect at over
105% of the rated current.
Overcurrent protection prevents the unit from short circuit and
overcurrent condition. The unit automatically recovers when the
fault condition is cleared.
1.3 Isolation
¡
For a receiving inspection, such as Hi-Pot test, increase (de-
crease) the voltage gradually for a start (shut down). Avoid using
Hi-Pot tester with timer because it may generate voltage a few
times higher than the applied voltage, at ON/OFF of a timer.
¡
In the case of use in locations exposed to constant voltage be-
tween primary and secondary is applied, please contact us.
1.4 Remote ON/OFF
¡
You can turn the power supply ON or OFF without turning input
power ON or OFF through the pin terminal RC.
¡
Please keep the voltage level of the pin terminal RC(V
RC
) at 9.0V
or below.
1.5 Output Voltage Adjustment Range (MHFS3)
¡
The output voltage is adjustable through an external potentiom-
eter.
¡
To increase the output voltage, turn the potentiometer so that the
resistance value between 2 and 3 becomes small.
¡
Please use a wire as short as possible to connect to the potenti-
ometer and connect it from the pin on the power supply side. Tem-
perature coefficient deteriorates when some types of resistors and
potentiometers are used. Please use the following types.
Resistor
Metal Film Type, Temperature Coefficient of
±100ppm/
C
or below
Potentiometer Cermet Type, Temperature Coefficient of
±300ppm/
C
or below
¡
When the output voltage adjustment is used, note that the output
may be stopped when output voltage is set too high.
Resistor R2
External
External
Potentiometer
Resistor R1
External
Output
TRM
-Vout
+Vout
3
1
2
Load
(a) Single Output
Fig.1.3 Connecting External Devices
Table 1.2 List of External Devices
Output Voltage
Constant of External Device [
W
]
Potentiometer
R1
R2
3.3V (-5%, +10%)
1k
680
150
5V (-5%, +20%)
1k
330
33
9V (-5%, +20%)
5k
6.8k
680
12V (-5%, +20%)
5k
12k
1.2k
15V (-5%, +20%)
5k
12k
220
DC-DC Converters PCB Mount Type
MH3
Instruction Manual
-Vin
+Vin
RC
3.3k
3.3k
External
Circuit
Control
Circuit
Fig.1.1 Internal Circuits of Remote ON/OFF
-Vin
+Vin
RC
-Vin
+Vin
RC
Input 12V
Input 24, 48V
Fig.1.2 Examples of Using an External Remote ON/OFF Circuit
Voltage Level of the pin terminal RC (V
RC
)
Output
Open or Short or 0V
[
V
RC
[
0.3V
ON
2.0V
[
V
RC
[
9.0V
OFF
Table 1.1 Pin Specification of Remote ON/OFF
MH-9
June 26, 2020
