User Manual

ManualsBrands3B Scientific ManualsIndustrial & ScientificDC Power Supply, 0-20V

3B Scientific GmbH • Rudorffweg 8 • 21031 Hamburg • Germany • www.3bscientific.com

Subject to technical amendments

2. Description

The 0 – 20 V, 0 – 5 A DC power supply provides a

DC voltage up to 20 V and a DC current up to 5 A.

The output voltage and output current are con-

tinuously variable. The unit can be used either as a

constant voltage source with current limitation or

as a constant current source with voltage limita-

tion. When the cv LED is illuminated it shows that

the unit is operating as a constant voltage source,

whereas the cc LED shows that it is operating as a

constant current source. The output is protected

against short-circuiting.

The U33020-115 DC power supply is for operation

with a mains voltage of 115 V (±10%), and the

U33020-230 unit is for operation with a mains

voltage of 230 V (±10%).

3. Technical data

Mains voltage: see rear of housing

DC output: 0 – 20 V, 0 – 5 A

Output power: 100 W

Stability under full load:

≤0,01% + 5 mV,

≤0,2% + 5 mA

Residual ripple:

≤1 mV, 3 mA

Displays: 2 x 3 digit LED

Primary fuse: see rear of housing

Terminals: 4 mm safety sockets

Dimensions: 130x150x300 mm

ap-

prox.

Weight: 4.7 kg approx.

4. Operation

4.1 General information

• Before switching on the power supply, set the

current and voltage regulators to zero (turn

fully to the left).

• Connect the power supply to the experimental

setup.

• Do not switch the power supply on until the

experiment has been fully assembled.

• Changes to the experimental setup must only

be made with the power supply switched off.

• Set the current regulator to give the required

current.

• Set the coarse and fine voltage regulators to

give the required voltage.

• Before switching off the power supply, set the

current and voltage regulators to zero again

(turn fully to the left).

4.2 Changing the fuse

• Turn off the power switch and unplug the

mains plug.

• Unscrew the fuse holder on the rear side of the

housing with a screwdriver.

• Replace the fuse and reinsert the holder in its

socket.