Briggs & Stratton 86262GS, Familiarization & Troubleshooting Manual

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UNITS OF ELECTRICAL MEASUREMENT
Section 1 • Generator Fundamentals
Portable Generator Familiarization & Troubleshooting Guide
Just as a hydraulic system must have specific values:
• Rate of flow.
• Pressure.
• Resistance to flow.
Relavent established values can also be expressed for an
electrical circuit. Fluid flow values in a hydraulic system are
generally expressed as:
• Gallons per minute.
• Pounds per square inch.
• Pressure drop or pressure differential.
Electron flow (current) through a conductor can be
compared to the flow of hydraulic fluid through a hose
(Table 1.2).
The units of measure for an electrical circuit are:
• Volts - Pressure.
• Amperes - Rate of Flow.
• Ohms - Resistance to Flow. (Figure 1.16)
Ampere - Unit of Current Flow
The rate of electron flow through a conductor is measured
in amperes, which is a measurement of electrons flowing
past a given point in a given time. One ampere is equal to a
little over six thousand million billion electrons per second!
Written numerically, the figure looks like this:
6,000,000,000,000,000,000.
Volt - Unit of Pressure
The volt is a measurement of the difference in electrical
potential (EMF) that causes electrons to flow in a circuit.This
difference in electrical potential (or electro-motive force)
may be described as the difference between the number of
positive charges and the number of negative charges.Thus,
voltage may be described as the potential of electrical
unbalance and current flow is the attempt to regain that
balance.
One volt is the amount of electro-motive force (EMF) that
will result in a current (electron) flow of one ampere
through a resistance of one ohm.
Ohm - Unit of Resistance
The electron may be compared to an individual trying to
make his way through a crowd of people, meeting the
resistance of human bodies every step of the way. In any
conductor or circuit, there is a resistance to electron flow.
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Table 1.2 — Hydraulic Flow Versus Current Flow
Figure 1.16 — Electrical Measurement Units