B&K 0-3A User Manual

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APPLICATION 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
22 
 
ELECTRONICS DESIGN LAB 
 
The technician or engineer working in an engineering laboratory 
requires a dc power supply to power breadboard and prototype 
circuits. This power supply is ideal because it monitors output 
current, output voltage, limits current to protect the circuit, is 
adjustable over a wide range, and has excellent regulation and very 
low ripple. 
 
Use of the instrument in an engineering laboratory is very 
similar to that described for servicing electronics equipment and 
modules, except that lower currents may be prevalent when 
powering individual circuits. The current limiting feature is very 
valuable in this application because it can protect unproven circuits 
from damage. 
 
ELECTRONICS EDUCATION 
 
The student in an electronics curriculum may use the power 
supply for powering equipment and circuits as previously 
described for all other applications. In addition, the power supply 
can be used in the classroom laboratory to conduct experiments in 
fundamental electronics. In learn ing Ohm’s law, for example, the 
relationships of resistance, current, and voltage are easily 
demonstrated by the use of a power supply. 
 
BATTERY CHARGING 
 
The power supply can be used as a battery charger to 
restore the charge in rechargeable batteries such as lead-acid, 
nickel-cadmium, and some alkaline types. Refer to the 
battery manufacturer’s charging specifica tions for proper 
voltage and current settings. Charging information is 
sometimes printed on the batteries. Battery charging, at least 
initially, requires the constant current mode of operation. 
Before connecting the power supply to the battery, preset the 
VOLTAGE controls to the fully charged terminal voltage 
specified by the battery manufacturer. Turn off the power 
supply while connecting the battery. Observe proper polarity 
and connect as for constant current operation. Adjust the 
CURRENT control for the maximum charging current 
specified by the battery manufact urer. (If the maximum 
charging current is greater than the power supply’s maximum 
load current, set the  CURRENT control to maximum). The 
CC indicator will light and the battery will charge at the 
preset current limit. As the battery approaches full charge, its 
terminal voltage will approach that of the power supply 
output and the charging current will taper off. The power 
supply may automatically switch to  CV (constant voltage) 
operation. When this occurs, the power supply will continue 
to provide a trickle  charge.