The Schonstedt Instrument Company provides solutions
for the detection and location of ferrous objects and
utilities below the surface of the ground or water.
Founded in 1953, the Schonstedt Instrument Company
designs and manufactures instruments for location of
underground objects. Schonstedt offers both pipe &
cable locators and magnetic locators.
The purpose of this article is to briefly explain
the differences
in each Schonstedt Underground Locator model, and the features they offer.
First, we'll mention that they're all called
"Underground Locators". Some people call them
Utility Locators, Yellow Sticks, or sometimes Metal
Detectors.
Schonstedt Instrument Company basically makes two
different types of Underground Locators. The first
is a "Magnetic Locator", and the other is a "Pipe
and Cable Locator". We will explain the basic
differences and how they work in this article. This will allow you
to hopefully learn more about the differences in the
various models and figure out which model best suits the
tasks that you'll use your Underground Locator for.
Magnetic Locators
You'll need to understand that Magnetic Locators
will ONLY locate metal objects that are made of ferrous material. Basically speaking, if a
magnet will stick to it, a Magnetic Locator will
detect it. Please understand that how deep in the
ground you can detect something depends on it's
mass. A surveying nail you can find up to about 2,
maybe 3 feet. An underground storage tank you can
find up to about 15 to 17 feet deep. Magnetic
Locators will not detect objects such as electrical
power cable made of aluminum or copper, since these
materials are not considered ferrous. Items that are
found using Magnetic Locators are usually cast iron
pipes, property corner markers, steel enclosures or
hardware, hazmat
drums, mag & pk nails, manhole and handhole covers,
marker magnets, septic tanks, unexploded ordnance,
curb & valve boxes, weapons, and well casings.Pipe and Cable Locators
With Pipe/Cable Locators, they do NOT detect
metal objects like a magnetic locator does. A Pipe/Cable
Locator will ONLY locate objects that have some type
of "charge" or "signal" placed on them. Many
utilities "give off" or transmit a signal of their
own that is sometimes detected by a Pipe/Cable
Locator such a 60Hz for live for power lines. But, sometimes the person doing the
locating must induce a signal onto the line in order
to be able to locate it. Most Pipe/Cable Locators have
the ability to "induce" a signal onto an object
(like a waterline) using a Transmitter, and the
object must be metallic in order to conduct the
signal. Pipe/Cable Locators typically come with a
receiver and a transmitter but not always. It
depends on the model you purchase. Some models come
with a portable pocket-sized transmitter with
limited features, and some come
with standard transmitters that are built into a hard
case and offer more features for varied situations. To simply describe how a Pipe/Cable Locator
works, the transmitter is just like a radio station
that's putting out a signal, and to pick up the
radio station you want to listen to (for example
your favorite rock music station) you need a
receiver. Just like radio stations, the transmitters
transmit signals in certain frequencies. Some
Pipe/Cable Locators come from the factory with
multiple signals to choose from, and some come from
the factory with a single frequency that you decide
and select before the purchase. To induce a signal
onto a pipe or cable, the Transmitter along with Signal Clamps or Alligator
Clips that
you place or fasten around on onto pipe, fire hydrants, cables,
and other utilities or lines that you're wanting to
locate. When accessibility to the utility’s
end-points (above ground) are not known, the
transmitter can also induce a signal from above,
through the ground to reach the utility. This allows the Transmitter to send it's
signal onto the pipe or cable you're wanting to
locate. Some Pipe/Cable Locator models come with the
accessories like Signal Clamps and Alligator Clamps
or Inductive Antennaes,
and sometimes you have to purchase the accessories
separately. Items that are found using Pipe/Cable
Locators are usually cable TV lines, fiber optic
lines with a metallic conductor along side, irrigation lines, plastic pipe or conduit
(plastic pipe can be located by inserting a sonde or
mini-transmitter and locating the sonde), plastic
pipe tracer wire, power lines, streetlight power,
and water lines.
Now hopefully you have a better understanding of how
a Magnetic Locator, and a Pipe-Cable Locator works.
Underground Locator Model Suggestion
Hopefully this will help you quickly figure out
which model is suggested for the job. It basically
depends on what you want to accomplish with your new
Underground Locator, so start out by asking yourself
and your co-workers, exactly what do you want to
accomplish with an Underground Locator.
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Magnetic
Locators |
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Schonstedt Magnetic Locator GA-52Cx
This is the work-horse model. It has audio
only, as it does not have a visual display. It's
the most popular selling model.
Schonstedt Magnetic Locator GA-72Cd
This model is the same as the GA-52Cx only it has a
handle, Audio, as well as an LCD visual display,
which displays polarity and signal strength.
The display helps define the outer edges of
the target.
Schonstedt Magnetic Locator GA-92XTd
This model has an expanding and
retractable body. Makes it easier to carry
in the field, and easier to store in small
places (behind your truck seat for example).
This model has an LCD visual display which
displays polarity and signal strength. The
display helps define the outer edges of the
target.
Schonstedt Magnetic Locator GA-92XTi
This model has an expanding and
retractable body. Makes it easier to carry
in the field, and easier to store in small
places (behind your truck seat for example).
It has audio only.
Schonstedt Magnetic Locator MAC-51Bx
This model doubles as a Magnetic Locator and
a Pipe/Cable Locator, as it comes with a the
Locator as well as a Transmitter. |
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Pipe and Cable
Locators |
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Schonstedt XTpc Pipe & Cable Locator
This is the most portable Pipe & Cable
Locator as it has an expanding and
retractable body. It comes with a
pocket-sized Trasmitter. It is made in two
frequencies. You select a single frequency
before purchase.
Schonstedt TraceMaster II Pipe & Cable
Locator TMS-001-AF
The AF stands for "All Frequencies".
This model includes all 4 frequencies
+ passive (60 Hz). The 4 included frequencies are
575Hz, 8kHz, 82kHz, and 455kHz. Has a unique
radio link to change frequencies in the
receiver like a remote.
Schonstedt TraceMaster II Pipe & Cable
Locator TMS-001-MF
Like the AF without the remote radio link.
This model includes all 4 frequencies +
passive (60Hz). The 4 included frequencies
are 575Hz, 8kHz, 82kHz, and 455kHz.
Schonstedt TraceMaster II Pipe & Cable
Locator TMS-001-PF-60
The TraceMaster PF (Passive/60 Hz only) does
NOT come with a transmitter, it is a
"Receiver Only" unit. The TMS-001-PF60 is
Passive Mode only.
Schonstedt TraceMaster II Pipe & Cable
Locator TMS-001-SF
The SF has a single frequency + passive.
You will need to specify frequency when
ordering. Choices of frequencies are; 575Hz,
8kHz, 82kHz, or 455kHz.
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