1 Functions

1.1 Input Voltage Range

¡

If output voltage value doesn’t fall within specifications, a unit may

not operate in accordance with specifications and/or fail.

1.2 Overcurrent Protection

¡

Overcurrent Operation

An overcurrent protection circuit is built-in and activated over

105% of the rated current or above. It prevents the unit from short

circuit and overcurrent for less than 20 seconds. The unit auto-

matically recovers when the fault condition is removed.

¡

Current Foldback Characteristic

If a model that has a current foldback characteristic is connected

to a non-linear load such as lamp or motor, or to a constant cur-

rent load, it may not start up. Please see the characteristics be-

low.

: Characteristic of Load (Lamp, Motor or Constant

Current Load, etc.)

: Load Characteristic of Power Supply

A

V

100

Load Factor [%]

Note : The output may be locked out at Point A when the unit is

connected to a lamp, motor or constant current load.

Fig.1.1 Current Foldback Characteristic

1.3 Isolation

¡

When you run a Hi-Pot test as receiving inspection, gradually in-

crease the voltage to start. When you shut down, decrease the

voltage gradually by using a dial. Please avoid a Hi-Pot tester

with a timer because, when the timer is turned ON or OFF, it may

generate a voltage a few times higher than the applied voltage.

¡

In the case of use in locations exposed to constant voltage be-

tween the input and the output of the unit is applied, please con-

tact us.

1.4 Output Voltage Adjustment Range

¡

The output voltage is adjustable through an external potentiom-

eter. Adjust only within the range of ±5% of the rated voltage.

¡

To increase the output voltage, turn the potentiometer clockwise

To decrease the output voltage, turn the potentiometer counter-

clockwise.

¡

Please use a wire as short as possible to connect to the potenti-

ometer and connect it from the pin terminal on the power supply

side. Temperature 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

¡

If output voltage adjustment is not required, open the pin terminal

TRM.

¡

In the case of dual output, ±voltages are adjusted simultaneously.

R2

External Resistor

External VR

R1

External Resistor

Output

TRM

-Vout

+Vout

3

1

2

Load

Fig.1.2 Connecting External Devices

Table 1.1 List of External Devices

Item # Output Voltage

Constant of External Device [W]

(Adjustable within ±5%)

VR

R1

R2

1

3.3V

1K

100

100

2

5V

1K

100

270

3

12V

5K

10K

1.2K

4

15V

5K

10K

470

5

±12V

5K

18K

470

6

±15V

5K

18K

470

1.5 Remote ON/OFF (Excluding 1R5)

¡

You can turn the power supply ON or OFF without turning the in-

put power ON or OFF through the pin terminal RC.

(1) SU/SUC3/SUT3 and SU/SUC6/SUT6

¡

The output of the power supply turns ON when the pin terminal

RC is connected to the pin terminal -Vin. When the voltage of the

pin terminal RC is between 2.0 to 9.0V, the output of the power

supply goes OFF.

¡

When the voltage of the pin terminal RC is between 0.3 to 2.0V,

the output voltage value may be an uncertain value which is less

than the rated voltage.

¡

Please see the following diagram for how to use the pin terminal

RC.

-Vin

+Vin

RC

2.2K

47K

External

Circuit

Control

Circuit

Fig.1.3 Internal Circuits of Remote ON/OFF

DC-DC Converters PCB Mount Type

Instruction Manual

SU.SUC/SUT-52

June 26, 2020