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APPLICATIONS_______________________________________________________________________________________
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 and 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 learning 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 specifications 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
manufacturer (If the maximum charging current is greater
than the power supply’s maximum load current, set the
CURRENT control to maximum). The CONSTANT
CURRENT 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 constant voltage
operation. When this occurs, the power supply will continue
to provide a trickle charge.
SPLIT SUPPLY
Frequently, “split power supplies” are required for
amplifiers and other electronic circuits. The Model 1651A is
ideally suited for “split power supply” operation. This supply
can be configured to provide two positive voltages with a
common negative, two negative voltages with a common
positive, or one positive and one negative with a common
ground. In addition, each of these configurations can be
obtained with identical or differing voltages.