BK Precision 1651A, Инструкция по эксплуатации

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APPLICATIONS
GENERAL
The Model 1651A power supply has a very wide variety of
applications in electrical and electronics servicing, engineering
laboratories, manufacturing and testing facilities, schools, and
home hobbying. The “A” and “B” power supply outputs are
fully adjustable from 0-to-24 volts and 0-to-0.5 amps and the
FIXED 5 V supply has a current capability of 0-to-4 amps.
This flexibility makes it suitable for most applications requiring
a dc power source.
ELECTRONICS SERVICING
Most electronics troubleshooting and repair is performed on a
test bench. This power supply can provide the dc power source
to operate a module or circuit board on the test bench when it is
removed from its parent equipment. It can be used to power
portable, battery-operated equipment and check the effect of
low battery voltage. It can power some vehicular equipment
such as tape players, auto sound systems, CB radios, etc. on the
test bench. Parallel tracking supplies up to 1 amp.
Most automobiles and other vehicles use 12-volt electrical
systems. Although the electrical system is normally referred to
as a 12-volt system, actual battery voltage when fully charged
is approximately 13.8 volts. The power supply may be set to
13.8 volts for servicing equipment from vehicles with 12-volt
electrical systems. Some trucks use a 24-volt electrical system;
bench testing of equipment from these systems should be
performed at approximately 28 volts.
Some servicing applications require the injection of a
variable dc voltage for certain tests, such as checking the
effect of AGC bias in a television receiver. This requires an
isolated dc power supply, such as the Model 1651A. The
equipment being tested may contain its own power supply
and operate from ac power. A dc voltage may already be
present in the circuit. One polarity of the power supply
output is floated to an appropriate point in the circuit, such as
the emitter of a transistor. The other polarity of the power
supply output is then applied to another point in the circuit,
such as the base of that transistor. Varying the power supply
voltage then varies the dc bias on the stage, and the effects
may be noted. A series limiting resistor is often used to
protect the circuits from overdissipation.
ELECTRONICS MANUFACTURING
In electronics manufacturing facilities, the power supply is
often used as a dc power source while testing and adjusting
modules, subassemblies, and complete units in the
production and assembly area or in the quality control area.
The instrument can be used in incoming inspection as a dc
power source for testing purchased components and
subassemblies.
This power supply is particularly well suited for
manufacturing applications because of its ease of operation
and its continuous duty rating. When load current or total
power dissipation are among the main characteristics to be
measured, the total load current and voltage are
simultaneously displayed on the panel meters. The current
limit can be set so that all units which do not meet the load
current specification will cause the
CONSTANT
CURRENT
indicator to light, and the unit can be rejected.