78-8130-6151-8 Rev G
21
Hz). Lower frequencies are less likely to ‘bleed over’ to other cables in the same
area, and are very good for tracing over long distances.
−
If the circuit reads more than 3K
Ω., but less than lOK Ω
(indicated by a
beeping tone from the transmitter) it will be necessary to use a higher frequency
than 577 Hz in order to locate the cable/pipe.
−
If the circuit reads more than lOK
Ω., it will be necessary to use an RF signal
such as 33 kHz or 133 kHz.
−
If there is no tone and the transmitter indicates that there is an open circuit (OL
in the display) this could be an indication of a poor ground, or an open-ended
cable or pipe. Use one of the higher frequencies available, at high or maximum
power output level. If it is an open-ended cable or pipe, the receiver's response
will decrease suddenly at the site of the clear or severed end.
Note: In the ohms mode, the transmitter can detect voltage as well as ohms. If a low
voltage is detected, the display will alternate between displaying ohms and volts. When
displaying ohms, the flag over the
Ω
symbol will be visible. When displaying volts, the
flag over the ‘V' will be visible. When the voltage magnitude is sufficient to impair
the accuracy of the ohms measurement, only voltage will be displayed. If the voltage
is AC, a sine wave will be visible on the Digital Display [T-4]. If a high AC voltage is
detected, a rapid beeping tone will be heard.
3. Press
Trace
[T-3] repeatedly until the desired frequency appears on the display.
Note that the number that flashes alternately with the selected frequency is called
the relative current. This number can be useful in identifying the target cable/
pipe and is discussed more in
8. Depth and Current Estimate
and
10. Locating in
Directional Peak Mode
.
4. Press
Output Level
[T-5] to select high or maximum power output level for longer
tracing distances or deep pipe/cable.
B. 3M™ Dyna-Coupler Method
!
WARNING
This WARNING applies to the following 3M Dyna-Couplers;
• 3" (75 mm) - Part number 3001
• 4.5" (114 mm) - Part number 4001
• 6" (150 mm) - Part number 1196
• All accessory kits containing any of the listed Dyna-Couplers - Part numbers 3019, 4519,
1196/C
A potential for electrical shock exists when using the Dyna-Coupler on cables energized with
electrical power. Use appropriate safety procedures.
DO NOT USE ON CABLES CARRYING IN EXCESS OF 600 VOLTS RMS.
