Page 11 - March-April2021 Vol 38 No 7

network for traffic signal systems within
the City of Memphis. The GIS database
also allows SSR to create field apps that
can be used to locate underground fiber
optic cable on location.
To keep the GIS system up to date, SSR
communicates with other engineering
firms and Construction, Engineering, and
Inspections (CEI) groups to receive plans
and as-builts for the fiber optic system.
TSM also alerts SSR to any missing fiber
that has been found or if the fiber optic
GIS database is showing fiber optic cable
in an incorrect area. Updates to the system
happen regularly.
GIS updates must be updated for each
firm using the platform. Each firm’s
system requires a different set of rules
to function properly. For SSR’s system,
the State Plane coordinate system
for Tennessee (NAD 1983 StatePlane
Tennessee FIPS 4100 (US Feet)) is used.
The SSR GIS database contains much
more information than is needed for
TN811 and KorTerra systems. The
information must be extracted separately
for both TN811 and KorTerra. TN811
uses the same coordinate system as SSR;
however, KorTerra uses WGS 1984, which
requires the data to be projected to that
coordinate system.
SSR also has a website created
specifically for Traffic Signal Maintenance
that allows them to download their
data as well as view the fiber map and
a map showing all the current locate
emergencies.
The Locator
The locator currently in use is the
Schonstedt XTpc (Figure 2). This pipe
and cable locator connects to the tracer
wire which allows a field technician to
follow the fiber line above ground. The
procedure for using the locator to find
tracer wire is as follows: First, the lid is are submitted with a locate deadline that
removed from the pull box. The positive
wire from the transmitter is then attached
to the tracer wire. Occasionally, the tracer located by law before the specified date
wire must be stripped to get contact.
Next, the negative wire is grounded.
Grounding can be achieved by attaching
the negative wire to a ground rod in the
kit, a bolt head inside the pull box, or to
a ground wire on a nearby utility pole.
The better the grounding connection, the
better the accuracy of the trace will be.
Once the wire has been grounded,
the transmitter is activated. When the
transmitter is reading the tracer wire
properly, the XTpc receiver is activated.
Figure 2. The picture on the left is the transmitter, while the picture on the right is the receiver.
The receiver displays the gain number. If
the number is too high, it thinks the wire
is everywhere.
If the gain number is too low, it cannot
locate the tracer wire. Upon achieving a
proper gain number, the field technician
walks in the direction indicated by the
receiver. The receiver lets the technician
know which direction to walk by displaying
arrows that indicate the direction of the
fiber optic cable.
If the receiver displays arrows on the left
and right, the technician knows that they
are in the middle of the fiber optic cable
location, and they paint an orange line on
the ground to locate the cable so that it can
be avoided during excavation activities.
Emergencies
Emergencies can occur at any time.
Emergency locates are instigated by a
litany of causes which include, but are not
limited to, downed poles, a contractor
digging in the wrong area, or a natural
disaster. An SSR field technician is on call
24/7. Whenever an emergency ticket is
issued, the field technician has two hours
to determine if the area indicated in the
emergency is in conflict or if it is clear,
and, if it is in conflict, to go to the site and boxes, so the first task is to locate a pull
physically mark the location of the fiber
optic cable.
There are several subcategories
of emergency tickets. These ticket
subcategories are short notice, emergency
impending, and emergency. Short notice
tickets are submitted with a locate deadline
that occurs before the 72 hours allotted
for standard tickets to be located. These
tickets are requested by the caller to be
located before the specified date and time
on the ticket.
Emergency impending tickets
occurs before the 72 hours allotted for
standard tickets. These tickets must be
and time on the ticket. Each ticket marked
with one of these categories is sent to
the emergency ticket e-mail and must be
located within two hours of receiving the
e-mail, by law.
The Field App
The field app used by SSR is an Esri
product called Collector (Figure 3).
Collector is used to upload a survey from
the Esri Survey123 app, which, in turn, is
used to answer specific questions about
the emergency. The Survey123 app is then
integrated into the Collector app.
The Collector app allows the field
technician to see their position relative
to the fiber optic line and pull boxes. The
app can be adjusted to show street names
or aerial imagery, whichever is most
convenient to help the field technician
locate pull boxes.
The field app is used to determine if an
area is in conflict. The field app displays the
location of the fiber optic lines, pull boxes,
and cabinets. When on site to perform a
utility location, field technicians can view
the map to orient themselves.
Tracer wires are located within the pull
box. Once the tracer wire is located inside
the pull box, it is used to guide the painted
markings used by construction crews to
avoid the fiber optic line during excavation.
To close out a site visit, the app is used
to mark the location of the site visit, take
pictures of the painted markings on the
ground, and enter the ticket number
associated with the emergency. This
provides documentation of the completed
utility locations in the field (Figure 4).
These updates are automatically uploaded
to the online map upon completion. The
final step for a site visit is closing the
emergency ticket in the TN811 Positive
Response portal.
Challenges with Locating
The biggest challenge that field
technicians face is the lack of a tracer wire
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