Current through Vol. 24-16, September 15, 2024
Rule 1.
(1) As used
in these rules:
(a) "Alternating current"
(AC) means a current that flows in and through a conductive material, first in
one direction and then in the opposite direction on a regular time
interval.
(b) "Ampere" means a
measure of the rate of flow of electric current through a conductive material.
A milliamp (the unit of measure commonly used for stray voltage measurements)
is 1/1,000 (0.001) of an ampere.
(c) "Animal" means vertebrates including, but
not limited to, dairy and beef cattle, sheep, swine, poultry and
horses.
(d) "Animal contact
current" (AcC) means an AC electrical current that is measured, calculated, and
may potentially flow through an animal due to an electrical contact voltage
between 2 points simultaneously in contact with the animal at locations
normally accessible by the animal.
(e) "Animal contact voltage" (AcV), commonly
referred to as stray voltage, means the measured difference in an AC electrical
potential when measured with a shunt resistor between 2 points that an animal
can simultaneously contact in locations normally accessible by the
animal.
(f) "Commission" means the
Michigan public service commission.
(g) "Communication service provider" means a
supplier of telecommunication or other electronic media services.
(h) "Cycle" means 1 complete positive and 1
complete negative alternation of current or voltage.
(i) "Direct current" (DC) means a current
that flows in only 1 direction, in and through a conductive material.
(j) "Harmonics" means a repeating sine wave
that fits within the main sine wave. The main sine wave is 60 cycles per second
(60 Hz) and is called the fundamental frequency. Harmonic currents, which are
multiples of the fundamental current, result in sine wave distortion. This
distortion may be caused by electronic components in equipment, such as
variable speed motor drives and computers.
(k) "Neutral-to-earth voltage" (NEV) means an
AC electrical potential difference between a utility grounded neutral or
complainant grounded neutral and the earth.
(l) "Ohm" means a measure of electrical
resistance of a conductive material that limits the flow of electric
current.
(m) "Ohm's Law" means the
mathematical relationship between volts, amperes, and ohms. If any 2 of these
quantities are known, then the third can be calculated. A formula for this
relationship is:
Volts (pressure)
------------------------- = Amperes (current flow)
Ohms (resistance)
(n) "Preventive action level" means a steady
state animal contact current that meets or exceeds 2 milliamperes RMS using a
nominal 500 ohms resistor at 60 Hz from all sources, including off-premises and
on-premises sources.
(o) "Root mean
square" (RMS) means a measure of the effective energy value of a wave or cycle.
For regularly-shaped sine waves, the RMS value is 0.707 multiplied by the peak
value of the sine wave.
(p) "Shunt
resistor" means an electrical component resistor with a nominal resistance
value of 500 ohms (which simulates the electrical resistance of an animal)
placed in a circuit to measure animal contact voltage (AcV) and placed across
the input terminals of the voltage measurement device. Animal contact current
(AcC) is calculated by dividing the measured shunted voltage at an animal
contact location by the value of the shunt resistor.
(q) "Sine wave" means a smooth curve starting
at zero and building up to a maximum before decreasing back to zero. The curve
continues below the zero line, building to a negative maximum, returning to
zero to complete 1 cycle. The smooth curve repeats. The voltage and current in
an AC electrical circuit trace out the shape of a sine wave repeating 60 times
each second, or 60 Hz.
(r) "60
hertz" or "60 Hz" means alternating current (AC) electricity that completes 60
cycles per second. The frequency is the number of cycles per second expressed
as hertz (Hz). The utility industry in North America generates and distributes
power at 60 Hz, or 60 cycles per second.
(s) "Steady state" means a 1 minute average
of RMS voltage or amperage values.
(t) "Stray voltage," also referred to as AcV,
means the measured difference in an AC electrical potential when measured with
a shunt resistor between 2 points that an animal can simultaneously contact in
locations normally accessible by the animal through step or touch both inside
and outside of farm buildings.
(u)
"Transient" means a rapid change in current that produces a deviation from a
normal sine wave. It normally lasts for only a fraction of a cycle. If
repeating, it usually does so for only a few cycles. It is generally caused by
on- or off-site electrical circuit failures, switches opening and closing, and
motors starting and stopping.
(v)
"Utility" means an electric company, whether private, corporate, cooperative or
municipal, that provides electricity to a consumer.
(w) "Volt" means a measure of electric
pressure or energy level (voltage) between 2 points that can push electrons
through a conductive material.
"Electrical Tech Note - 231"; Agriculture Engineering
Department, Michigan State University; Figure 7, Page 6
Typical Harmonic Waveform
"The Handbook for Electric Metering -- ninth edition", Edison
Electric Institute, EEI Publication No. - 06-92-01, Figure 4-10 Page 62
(2) These definitions
are an application of the Institute of Electrical and Electronics Engineers
(IEEE) 100, "The Authoritative Dictionary of IEEE Standards and Terms," 7th
Edition. Printed copies of the dictionary are available from the Institute of
Electrical and Electronics Engineers 445 Hoes Lane, Piscataway, New Jersey,
08854, at a cost of $160 at the time of adoption of this rule. A printed copy
of the dictionary is also available at the Michigan Public Service Commission,
6545 Mercantile Way, Lansing, Michigan, 48911.