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99 Washington Street
Melrose, MA 02176
Phone 781-665-1400
Toll Free 1-800-517-8431
Visit us at www.TestEquipmentDepot.com
C9970
Voltage Detector
Users Guide
PN 1286912
May 2007 Rev. 3 3/10
©2007-2008, 2010 Fluke Corporation. All rights reserved. Printed in USA.
All product names are trademarks of their respective companies.
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LIMITED WARRANTY AND LIMITATION OF LIABILITY
Each Fluke Networks product is warranted to be free from defects in material and
workmanship under normal use and service. The warranty period for the mainframe is one
year and begins on the date of purchase. Parts, accessories, product repairs and services are
warranted for 90 days, unless otherwise stated. Ni-Cad, Ni-MH and Li-Ion batteries, cables
or other peripherals are all considered parts or accessories. The warranty extends only to
the original buyer or end user customer of a Fluke Networks authorized reseller, and does
not apply to any product which, in Fluke Networks’ opinion, has been misused, abused,
altered, neglected, contaminated, or damaged by accident or abnormal conditions of
operation or handling. Fluke Networks warrants that software will operate substantially in
accordance with its functional specifications for 90 days and that it has been properly
recorded on non-defective media. Fluke Networks does not warrant that software will be
error free or operate without interruption.
Fluke Networks authorized resellers shall extend this warranty on new and unused products
to end-user customers only but have no authority to extend a greater or different warranty
on behalf of Fluke Networks. Warranty support is available only if product is purchased
through a Fluke Networks authorized sales outlet or Buyer has paid the applicable
international price. Fluke Networks reserves the right to invoice Buyer for importation costs
of repair/replacement parts when product purchased in one country is submitted for repair
in another country.
Fluke Networks warranty obligation is limited, at Fluke Networks option, to refund of the
purchase price, free of charge repair, or replacement of a defective product which is
returned to a Fluke Networks authorized service center within the warranty period.
To obtain warranty service, contact your nearest Fluke Networks authorized service center
to obtain return authorization information, then send the product to that service center,
with a description of the difficulty, postage and insurance prepaid (FOB destination). Fluke
Networks assumes no risk for damage in transit. Following warranty repair, the product
will be returned to Buyer, transportation prepaid (FOB destination). If Fluke Networks
determines that failure was caused by neglect, misuse, contamination, alteration, accident
or abnormal condition of operation or handling, or normal wear and tear of mechanical
components, Fluke Networks will provide an estimate of repair costs and obtain
authorization before commencing the work. Following repair, the product will be returned
to the Buyer transportation prepaid and the Buyer will be billed for the repair and return
transportation charges (FOB Shipping point).
THIS WARRANTY IS BUYER’S SOLE AND EXCLUSIVE REMEDY AND IS IN LIEU OF ALL OTHER
WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY IMPLIED
WARRANTY OR MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. FLUKE
NETWORKS SHALL NOT BE LIABLE FOR ANY SPECIAL, INDIRECT, INCIDENTAL OR
CONSEQUENTIAL DAMAGES OR LOSSES, INCLUDING LOSS OF DATA, ARISING FROM ANY
CAUSE OR THEORY.
Since some countries or states do not allow limitation of the term of an implied warranty,
or exclusion or limitation of incidental or consequential damages, the limitations and
exclusions of this warranty may not apply to every buyer. If any provision of this Warranty
is held invalid or unenforceable by a court or other decision-maker of competent
jurisdiction, such holding will not affect the validity or enforceability of any other provision.
4/04
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Table of Contents
Title Page
Introduction ...................................................................................................1
Registration ....................................................................................................1
Contacting Fluke Networks ...........................................................................1
Safety Information .........................................................................................2
Care and Maintenance ..................................................................................3
Mechanical Shock .....................................................................................3
Environment .............................................................................................3
Water Resistance ......................................................................................4
Defacing or Altering the Housing ...........................................................4
Carrying the Voltage Detector ................................................................ 4
Storage ......................................................................................................4
Battery Replacement ................................................................................4
Safety Gloves ..................................................................................................5
Theory of Operation ......................................................................................5
Physical Description .......................................................................................6
Accessories ......................................................................................................7
Temporary Bond .......................................................................................7
Connecting the Temporary Bond ........................................................7
Disconnecting the Temporary Bond ...................................................7
Storage Bag ..............................................................................................8
Ground Cord .............................................................................................8
Test Plug ...................................................................................................8
Periodic Performance Tests ...........................................................................8
Self Check .................................................................................................8
Test Plug Threshold Test ..........................................................................10
Service Center Repair and Verification ...................................................10
Operation .......................................................................................................11
AC Hazardous Voltage Testing ................................................................12
DC Hazardous Voltage Testing ................................................................12
Aerial Testing ...........................................................................................14
Applications ....................................................................................................14
Ground Level ............................................................................................14
Telephone Cable Sheath ..........................................................................15
Damaged Cable Closure ........................................................................... 15
Base of Pole: Telephone Plant Repairs ....................................................15
Loose Plant ...............................................................................................16
Temporary Bond .......................................................................................16
Ungrounded Insulated Conductors .........................................................17
Traffic Lights .............................................................................................17
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C9970 Voltage Detector
Users Guide
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C9970 Voltage Detector
Introduction
The C9970 Voltage Detector is a high-voltage probe used for detecting hazardous
voltage on conductive objects such as power ground wires, street light fixtures,
mobile homes, metal frameworks, metal conduit, pedestals, newly-driven ground
rods, homes covered with metallic siding, and electrical machinery.
This manual describes the proper care and use of the C9970 Voltage Detector and
its accessories. Read this manual completely before using the Voltage Detector.
Registration
Registering your product with Fluke Networks gives you access to valuable
information on product updates, troubleshooting tips, and other support services.
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C9970 Voltage Detector
Users Guide
Safety Information
The following IEC symbols are used either on the Voltage Detector or in this
manual:
W
X
.
~
Warning: Risk of personal injury. See the manual for details.
Caution: Risk of damage or destruction to equipment or software.
See the manual for details.
Warning: Risk of electric shock.
Earth ground
Do not put products containing circuit boards into the garbage.
Dispose of circuits boards in accordance with local regulations.
WXWarning
To avoid possible electric shock or personal injury, follow these
guidelines:
•
Only qualified personnel who have been trained and are knowledgeable
about the dangers associated with hazardous voltages should use this
product.
•
Be sure to know and follow your company’s procedures for every
application. Any conflict between the procedures specified in this manual
and those of your company must be resolved before using the Voltage
Detector.
•
Do not use the Voltage Detector if it is damaged.
•
Before you use the Voltage Detector, inspect the case. Look for cracks or
missing plastic. Pay particular attention to the insulation surrounding the
connectors.
•
Do not use if wet.
•
Inspect the Voltage Detector for damaged insulation or exposed metal.
•
Do not use the Voltage Detector if it operates abnormally. Protection may
be impaired. When in doubt, have the Voltage Detector serviced.
•
Do not operate the Voltage Detector around explosive gas, vapor, or dust.
•
Do not apply more than the rated voltage, as marked on the Voltage
Detector, between terminals or between any terminal and earth ground.
•
Before use, verify the Voltage Detectors operation by measuring a known
voltage.
•
When servicing the Voltage Detector, use only specified replacement parts.
•
Use caution when working above 30 V ac rms, 42 V peak, or 60 V dc. Such
voltages pose a shock hazard.
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Care and Maintenance
•
Do not use in excess of the voltage specified in this manual.
•
When using probes, keep your fingers behind the finger guards on the
probes.
•
Remove any voltages from the Voltage Detector before accessing the
battery.
•
Do not operate the Voltage Detector with portions of the case removed or
loosened.
•
To avoid false indications, which could lead to possible electric shock or
personal injury, replace the batteries as recommended. See “Battery
Replacement” on page 4 for additional information.
•
Use only type 9 V batteries, properly installed in the Voltage Detector case,
to power the Voltage Detector.
WCaution
To avoid possible damage to the Voltage Detector or to the
equipment under test, use the proper terminals and function for your
measurements.
Care and Maintenance
Any Voltage Detector with confirmed or suspected damage to the plastic housing
(deep scratches, cracks, holes, etc.) or internal circuitry should never be used.
Mechanical Shock
Do not drop the Voltage Detector or subject it to severe mechanical stress which
may damage the protective insulation or internal circuitry. The Voltage Detector
should be tested and repaired if it appears to be damaged or fails to meet the tests
described in “Periodic Performance Tests” on page 8.
Environment
Do not expose the Voltage Detector to extreme temperatures (below -40 °C or
above +60 °C) or chemicals that may soften, crack, or otherwise damage the plastic
housing.
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C9970 Voltage Detector
Users Guide
Water Resistance
Although the Voltage Detector is water resistant, do not expose it to water. If
submerged in water, it must be dried completely and checked for proper operation
before use. (If a test plug is unavailable, a 110-120 VAC, 60 Hz source may be
temporarily substituted with caution.)
If the Voltage Detector appears to have taken on water, open it by unscrewing the
handle in a counterclockwise direction and allow it to dry completely before
closing. Do not attempt to remove the ground or check contacts or disassemble
the front portion of the test set. After closing, test the Voltage Detector with a test
plug before returning to use.
Defacing or Altering the Housing
Do not drill, punch, engrave, or otherwise modify the housing of the Voltage
Detector. Do not use adhesives, adhesive labels, inks, solvents, or expose to
chemicals which may alter the housing. Defacing or altering the Voltage Detector
may lower or destroy its sensitivity to hazardous voltages and will void the
warranty.
Carrying the Voltage Detector
Keep the conductive cap over the probe end of the Voltage Detector when it is not
in use to avoid damage to the tip and possible hazard to the user. The carbide tip is
sharp and should be treated accordingly.
Storage
Do not subject the Voltage Detector to possible pressure or damage from other
tools or material. Pressure may cause the switch to operate and discharge the
battery. Do not store the Voltage Detector near strong magnets.
Battery Replacement
When replacing batteries, work in a dry place. Always replace the battery with a
9 V alkaline battery.
WXWarning
Some imported 9 V batteries are slightly oversized. If an over- sized
battery is installed, the metal shield may be torn from the circuit
board.Therefore, if the replacement battery seems tighter than the
original, try a different brand of battery.
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Safety Gloves
To replace the battery, do the following:
1
Open the Voltage Detector body by unscrewing the handle in a counterclockwise direction and sliding it back from the front assembly. Do not
attempt to loosen the check contact or the ground terminal.
2
Gently slide the battery out of the metal shield, attach a new battery, and slide
it back into the metal shield. Be careful not to get the battery wires between
the metal shield and the side of the battery or to bend or distort the metal
shield.
3
Slide the handle over the shield and rotate in a clockwise direction until a
snug fit is secured. Make sure that the LEDs line up with the trigger, or the
probe switch may not operate. A snug fit is required for proper O-ring seal
and LED alignment, but it is not necessary to overtighten.
Safety Gloves
The Voltage Detector is designed to protect the user from exposure of up to
20,000 V, 60 Hz, AC. Using gloves reduces the sensitivity of the Voltage Detector
and may cause erroneous results (see “Theory of Operation” below). If protective
gloves are worn while using the Voltage Detector (or are required by company
procedures) and a hazardous voltage is indicated, do not retest without gloves.
Move away and refer to your company’s safety procedures. However, if the user is
gloved and a safe condition is indicated, perform a second test without gloves and
follow the results of this second test.
Theory of Operation
The Voltage Detector uses electronics and high-voltage mechanical design to
indicate the presence of dangerously-high AC and DC voltages. To do so, it first
determines the voltage difference between the user’s body and the object being
tested. Then, it compares that difference to an internal safety reference. If the
voltage difference exceeds this reference, the Voltage Detector indicates danger.
No interpretation of readings is required.
The capacitance between the handle of the Voltage Detector and the user’s hand
is part of the measuring circuit and can affect the sensitivity of the Voltage
Detector. Further, voltages induced onto the user’s body can also affect readings.
Such voltages can be induced when the user is isolated from ground while
working aloft near power transmission lines. These induced voltages can cause the
Voltage Detector to indicate danger when none actually exists. These induced
voltages are harmless, but must be discharged. The correct procedure is described
under “Aerial Testing” on page 14.
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C9970 Voltage Detector
Users Guide
Physical Description
The Voltage Detector, shown in Figure 1, is a yellow, plastic, two-piece, unit that
weighs approximately one pound.
The front housing includes the carbide probe tip and two LEDs (one green and one
red) along with a check contact and a ground terminal. These and the battery are
attached to the front housing.
The rear housing, which acts as a handle, includes a set of concentric rings (called
the flashguard), the on/off switch (called the trigger), an instruction label, and a
belt clip.
LEDs
Probe
tip
(red and green)
Ground terminal Trigger
contact
6
Check
Conductive
end cap
Flashguard
Figure 1. Voltage Detector
Instruction
label
Belt
clip
emu01.eps
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Accessories
Accessories
The following sections describe the accessories available for the Voltage Detector,
which are shown in Figure 2.
Temporary bondStorage bag
Ground cord Voltage Detector
emu02.eps
Figure 2. Voltage Detector and Accessories
Temporary Bond
The Voltage Detector temporary bond is used to temporarily ground a light
fixture, metallic conduit, power company hardware, power ground wire, or other
metallic objects in a work space that could become energized if a fault developed.
It is a heavy-duty insulated cord equipped with a large clamp on one end and a
smaller clamp on the other end.
Connecting the Temporary Bond
Connect the temporary bond only after the metallic object has first been tested
with the Voltage Detector and found to be free of a voltage potential.
To attach the bond, first connect the small clamp to a reliable ground source; then
connect the large clamp to the metallic object.
Disconnecting the Temporary Bond
When the work is completed, first disconnect the bond’s large clamp from the
metallic object; then disconnect the small clamp from the ground source. Should a
fault develop while the temporary bond is in place, the insulation may overheat
and smoke, at which time you should avoid contact with the bond.
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C9970 Voltage Detector
Users Guide
Storage Bag
The Voltage Detector storage bag holds the Voltage Detector and its accessories.
The bag’s interior is lined with plastic. The bag has a fabric strap with a metal snap
hook and a zipper closure.
Ground Cord
The Voltage Detector ground cord is used only in certain aerial applications where
the user is isolated from ground and near power transmission lines. The cord is a
25-ft retracting cord with clamps on each end. This cord, along with the conductive
plastic end cap, eliminates induced body voltage to prevent false hazard
indications.
Tes t Pl ug
The Voltage Detector test plug is used to verify the lowest voltage (threshold
voltage) at which the Voltage Detector indicates danger. It is an AC-operated plug
that provides a suitable, current-limited, reference voltage to verify proper
operation of the Voltage Detector. It plugs into a standard, ground-referenced,
power outlet. The test plug is current-limited and may be touched without
electrical shock, even while energized. The test plug consumes less than
30 milliwatts and may be left in an outlet indefinitely if desired.
Periodic Performance Tests
The Voltage Detector should be checked periodically to ensure that it is working
properly and that it retains its protective properties. There are two primary tests
that can be used to verify the integrity of the Voltage Detector: a self check and a
test plug threshold (sensitivity) test.
Self Check
Perform the self check before each use of the Voltage Detector to verify it is
working properly. To perform a self check, do the following:
1
Clean and dry the entire housing. Moisture, dirt, and other foreign matter
reduces the insulating properties of the plastic surface.
2
Examine the housing for cracks.
3
Grasp the handle with your bare hand. Press the trigger and observe the
green LED. If it does not illuminate or is very dim, check the internal battery
and replace if needed. If the green LED still does not illuminate, do not use the
Voltage Detector.
4
With the trigger pressed, use the free hand to touch both the probe tip and
the check contact (shown in Figure 3). The red LED should flash and the green
LED should go out. If they do not, the Voltage Detector is malfunctioning.
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Periodic Performance Tests
Note
It may be necessary to wet the fingers that are touching the probe tip and
check contact in order to start the red flashing LED. This is acceptable and
does not indicate a malfunctioning Voltage Detector.
5
Once the red LED starts flashing, remove the free hand while continuing to
press the trigger. The red LED should continue to flash as long as the trigger is
pressed. If it does not, the Voltage Detector is malfunctioning.
After passing the self check, the Voltage Detector may be used to perform a
voltage test. If it fails, contact Fluke Networks as described on page 1.
Figure 3. Performing a Self Check
emu03.eps
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C9970 Voltage Detector
Users Guide
Test Plug Threshold Test
While the self check verifies proper operation of most of the circuits, it does not
verify proper sensitivity of the Voltage Detector. Therefore, a test plug threshold
test should be performed to verify proper sensitivity, check the Voltage Detector’s
insulation, or after the Voltage Detector has been subjected to severe mechanical
stress.
This test should be performed at least weekly.
To perform a test plug threshold test, do the following:
1
Plug the test plug into a standard, 3-wire, 110-120 VAC outlet. The test plug
provides the proper reference voltage for the threshold test. (The test plug
draws little current and may be left in the outlet.)
2
Perform a self check (see page 8).
3
Touch the Voltage Detector to the screw head test point on the test plug. If
the Voltage Detector indicates danger (red flashing LED), it passes the
threshold test. If the Voltage Detector does not indicate danger (green LED is
on), it is malfunctioning.
Note
The integrity of the test plug can be verified with an ohmmeter. The
resistance from the test point to either or both of the two prongs should be
300 KΩ, ±1%. This test should be done each time you perform a Voltage
Detector threshold test. A faulty test plug should be discarded immediately.
WXWarning
Do not use any Voltage Detector that fails either the self check or test
plug threshold test. Remove the Voltage Detector from service
immediately and contact Fluke Networks as described on page 1.
Service Center Repair and Verification
Repair and verification of your Voltage Detector are available at any Fluke
Networks authorized service center. See the contact information on page 1.
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Operation
To use the Voltage Detector, do the following:
1
Before using the Voltage Detector, always perform a self check (see “Self
Check” on page 8).
2
Remove the black conductive end cap from the probe tip. Be careful not to
unscrew the front and rear housing while removing the cap.
3
Hold the Voltage Detector as shown in Figure 4.
4
Use your bare hand (except when gloves are required) to grasp the rear
housing and your thumb to operate the trigger.
Operation
Figure 4. Holding the Voltage Detector
emu04.eps
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C9970 Voltage Detector
Users Guide
AC Hazardous Voltage Testing
No grounding is required except when testing aloft near power transmission lines
(see “Aerial Testing” on page 14).
The Voltage Detector is designed to detect 60 Hz, AC hazards. At frequencies
below 60 Hz, the Voltage Detector requires higher voltages to trigger a hazard
indication. At frequencies higher than 60 Hz, the Voltage Detector requires less
voltage to trigger.
To test for hazardous AC voltage, do the following:
1
Perform a self check (see “Self Check” on page 8).
2
Press and hold down the trigger while approaching the object to be tested.
The tip must be the closest point to the object under test. If the red LED
flashes, immediately move away from the object. A high voltage is present
and you should not continue the test.
WCaution
When high voltages are present, move away immediately after a
hazard indication appears. Otherwise, the Voltage Detector may
momentarily arc. Though the user is protected from electrical shock,
this may be startling.
3
If no hazard indication appears while approaching the object, press the probe
tip against the object. It may be necessary to turn the Voltage Detector from
side to side to break through paint or other surface finishes or corrosion.
Ensure that a reliable contact is made.
4
To avoid false indications due to static electrical discharge, release and repress
the trigger while still making contact with the object. Ensure that a reliable
contact is maintained.
5
Still holding the trigger down, remove the Voltage Detector from the object
and observe the LEDs:
•
The green LED means a safe condition.
•
The red flashing LED means dangerous voltages are present.
DC Hazardous Voltage Testing
The Voltage Detector indicates the presence of DC voltages between 6 VDC and
2,000 VDC. When testing DC voltages, a connection must be established between
the ground terminal of the Voltage Detector and a known earth ground. This
connection may be made using a suitable insulated cord equipped with clamps on
each end, such as the temporary bond. At no time should the ground terminal on
the Voltage Detector be loosened. If there is any doubt as to the continuity of the
grounding cord used, test the cord before it is used to test for hazardous voltages.
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To test the continuity of a grounding cord, do the following:
1
Connect one end of the cord to the probe tip of the Voltage Detector. If you
are testing the temporary bond, connect the large clip to the tip.
2
Press and hold the Voltage Detector trigger.
3
Touch the other end of the cord to the Voltage Detector check contact. The
red LED should flash. Do not use the cord for testing if it does not pass this
test.
Note
This test verifies whether this ground cord can be used with the Voltage
Detector. It does not verify the cord’s current-handling ability for use as a
bond.
To test for hazardous DC voltage, do the following:
1
Perform a self check.
2
Perform an AC hazardous voltage test. If the AC hazardous voltage test
indicates no hazardous voltage, proceed. Otherwise, halt testing.
3
Prepare a temporary ground bond, such as the Voltage Detector temporary
bond, and test it as described above.
Operation
4
Press the probe tip against the object to be tested and press the trigger. It may
be necessary to turn the tester from side to side to break through paint or
other surface finishes or corrosion. Ensure that a reliable contact is made.
5
To avoid false indications due to static electrical discharge, release and repress
the switch while still making contact with the object. Ensure that a reliable
contact is maintained.
6
Still holding the switch down, remove the Voltage Detector from the object
and observe the LEDs:
•
The green LED means a safe condition.
•
The red flashing LED indicates hazardous voltages. If a hazardous voltage
is present, move away from the object and refer to your company’s safety
procedures.
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C9970 Voltage Detector
Users Guide
Aerial Testing
When working aloft in an insulated bucket or on a ladder where you are well
isolated from ground and near power transmission lines, the following procedure
is required to prevent false indications due to the voltage induced on you.
1
Put on company-required protective equipment, such as a hard hat, eye
protection, etc.
2
Place the conductive plastic probe end cap on the handle (clip end) of the
Voltage Detector. Push on until firmly in place.
3
Perform a self check.
4
Attach one end of the ground cord to a known earth ground. Attach the
other end of the ground cord to the contact knob on the end cap.
5
Ascend to a convenient height to make the voltage test. Do not come in
contact with the suspected hardware, light fixture, or its wiring.
6
Test the suspect object for hazardous voltage as described earlier and observe
the LEDs:
•
If after you press the trigger and touch the probe tip to the object, the
green LED remains illuminated and the red LED remains off, you may
proceed with your work after placing a temporary bond (see “Temporary
Bond” on page 7).
•
If the red LED flashes, a hazardous condition exists. Descend immediately
and refer to your company’s safety procedures.
Applications
Following are additional instructions and safeguards for more specific applications.
They expand the previous instructions, but do not replace them.
Ground Level
Mobile homes, trailers, metal sheath buildings, ground rods and electrical
machinery all present potential electrical hazards and always require testing.
Before starting any work operation, test the skin and frame (or both frames in the
case of double wide mobile homes).
In some cases, such as when driving a ground rod, you might wear rubber gloves
during the work operation. The final test must be done with the bare hand
holding the Voltage Detector.
If a voltage is detected, the property owner should be notified for corrective action
according to the user’s company procedures. Do not make contact with the
potential hazard until all hazardous voltages are removed and the Voltage
Detector indicates a safe condition.
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Applications
Telephone Cable Sheath
When sheath continuity is to be interrupted for the purpose of locating plant,
locating faults, or making splices, it is necessary to test the sheath with the Voltage
Detector prior to and after opening it.
Damaged Cable Closure
If a telephone, CATV, or power pedestal closure (all closures used in joint-buried
plant) has been damaged or disturbed, (for example, knocked over or hit by a car)
or a trouble condition involving power is suspected, contact the power company
first. Once the power company completes its work, the pedestal should be tested
before any bodily contact is made. However, work should not be done on
telephone or CATV plant until the power company has completed repairs.
If the Voltage Detector indicates a safe condition, remove the cover of the closure
and visually inspect the cable sheath ground. If the cable sheath ground is not
intact or is loose, test the cable sheath with the Voltage Detector before
performing maintenance work. If for any reason it becomes necessary to open the
bonds between telephone facilities and power or across cable sheath openings, a
temporary bond strap must be placed before the bond is opened. If the temporary
bond cannot be placed due to physical conditions, consult with the power
company representative. It may be necessary to de-energize the power briefly for
repair operations. When temporary or permanent bonds are placed or removed,
insulating gloves and eye protection must be worn.
WXWarning
Electrical continuity of all bonds, including cable shield bonds in
closure or at splice locations, must be preserved during the repair
process. Until the permanent bond is installed, maintain continuity
using a temporary bond strap.
Base of Pole: Telephone Plant Repairs
Examine the pole for potential electrical hazards such as a vertical power ground
wire, vertical metallic power conduit, street light fixture, power company primary
disconnect hardware, or other foreign metal objects. Also, observe the pole and
adjacent spans for such hazards as improper clearance from power conductors or
equipment, dangling power wires, inadequate clearance on pole-to-pole guys
from power wires or energized attachment, etc. If none of these is present, the
pole may be climbed providing no other hazard is evident.
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C9970 Voltage Detector
Users Guide
If a vertical power ground wire is present, make a voltage test of the wire before
climbing or working on the pole. If a vertical metallic power conduit or other
power company hardware extends to the base of the pole, make a voltage test
before climbing or working on the pole. If the ground wire is broken, test the
portion going up the pole unless the break exists above the telephone space. Do
not attempt to test a broken ground wire or fixture in the power company’s space
(40 inches or more above the highest telephone attachment). Refer to your
company’s safety procedures.
If the Voltage Detector does not indicate a hazardous voltage, poles carrying
vertical power ground wires may be climbed. Care should be taken to avoid
simultaneous contact between power ground wires and telephone cable or guys
since a small voltage may be present. This is recommended to avoid the possibility
of a shock that might cause a fall from the pole.
If an ungrounded street light fixture is less than 40 inches above or below
telephone attachments and is on a pole not carrying a telephone cable or a bare
vertical power ground wire, wear insulating gloves. Since it is not possible to place
a temporary bond to an effective ground, you should avoid contact with the
fixture.
WCaution
Do not make contact with supply wires going to the fixture.
Loose Plant
In general, you should avoid unsecured objects, dangling wires, etc., which would
tend to move if probed. Breaking through corrosion is difficult in such cases and
there is a danger that the object might suddenly swing around and hit you.
Temporary Bond
The temporary bond is used to temporarily ground a fixture, conduit, or bare
vertical ground wire which has been tested for and found to be free from a
voltage potential while working aloft. Should a fault develop, the temporary bond
will provide a direct path to ground for the foreign potential. The insulation on
the bond may overheat and smoke which should alert you to descend the pole.
Using insulating gloves, attach the bond in the following manner:
1
Attach the small clip of the temporary bond to the cable suspension strand in
such a manner that it will not be in the way of work operations.
2
Attach the large clip of the bond wire to the fixture, conduit, or bare vertical
ground wire. Do not bond to a support bracket of multiple line wire or the
suspension strand of isolated cable. Never attach to street light wires,
terminals that wires are attached to, or a fixture that causes the red LED to
flash.
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Applications
Insulating gloves may be removed only after the temporary bond is in place, and
then only if other protection requirements permit. Leave the temporary bond in
place until all work operations are complete at this pole for the day. If the bond
starts smoking, put on insulating gloves and descend the pole immediately. In that
case, avoid contact with the bond, the fixture, or its wiring and refer to your
company’s safety procedures.
Upon completion of work operations on a pole, remove the temporary bond by
doing the following:
1
Put on insulating gloves.
2
Remove clip from the fixture, metallic conduit, or bare vertical ground wire.
3
Remove the other clip, which was attached to the strand. If a spark is detected
when removing the bond, descend the pole immediately and refer to your
company’s safety procedures.
Ungrounded Insulated Conductors
Insulated conductive objects in the presence of live AC current may tend to act as
antennae for AC potential. If these test as unsafe, they should be treated as such
and avoided.
Traffic Lights
Particular care must be taken when working near traffic light wiring or other
wiring which may become energized momentarily. Voltage tests made during one
part of a cycle may not be valid during another part.
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