BASIC ELECTRONICS - OD1633 - LESSON 1/TASK 1
has a 20 percent tolerance, a silver fourth band has a 10 percent tolerance,
and a gold fourth band has a 6 percent tolerance. In some cases, the third
band will be silver or gold. It then becomes a multiplier, and you multiply
the first two bands by 0.01 if it is silver, and 0.1 if it is gold.
Resistors that conform to military specifications have an additional fifth
band.
The fifth band indicates the reliability level per 1000 hours as
follows:
Fifth band color
Level
Brown
1.0%
Red
0.1%
Orange
0.01%
Yellow
0.001%
In applying the reliability level table for a resistor color coded brown,
the chance of failure will not exceed 1 percent for every 1000 hours of
operation of that resistor.
In a piece of equipment containing 10,000
orange fifth band resistors, it means that no more than one resistor will
fail during 1000 hours of operation. This is very good reliability.
Both wirewound and composition resistors will not use the resistor color
code. These resistors will have the ohmic value and tolerance imprinted on
the resistor itself.
7.
Conclusion
In this task, we covered the elements of electricity, safety requirements to
be used when working around electricity, voltage, current, resistance
functions, Ohm's law, and resistor color codes.
In the next task, we will cover series, parallel, and series-parallel
circuits. We will also measure and compute voltage and current of batteries
connected in series--parallel circuits.
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