18 Mar 10 Tips For Better Cable Locating
When it comes to cable locating, safety, accuracy and efficiency are of top concern. Here are 10 quick tips for better cable locating from Norscan’s own cable locating expert, Walter Motuz.
Next Level Cable Locating
Always exercise standard safety procedures when performing a cable locate. Assume that every target locate area can present an element of risk and danger, so prepare accordingly.
Scope it out
Scope out the target locate area and reference all as-built draws to gain a good understanding of how your cable will intersect with the work site area.
Direct Connect for a Better Signal
On non-energized conductors, direct connection to the cable conductor (cable armor/sheath or tracewire) and the use of locate signal transmitter equipment is the best practice. This ensures a more accurate locate of your cable because the locate signal will be emanating from your cable and will therefore have the strongest locate signal.
establish a Good Local Ground Signal Return Path
Establishing a good local ground signal return path at the end of the target locate area is essential for all cable locating routines. Cable locate signals need to be drawn down a cable conductor to ensure the presence of a locate signal. Poor ground return paths will limit the cable locate distance and signal strength of the locate signal being transmitted.
Use Lower Frequency Locate Signals
Lower frequency locate signals reduce the risk of your cable signal coupling onto other utilities and will increase the locate signal distance that can be traveled on the cable conductor. Best transmitter locate frequencies range between 200Hz and 600Hz and if you are using a Touchless Locate transmitter, locate distances of 60 miles or 100 kms can be reached within this range.
Different Markers for Different Environments
Use the most appropriate marking methods to illustrate the presence of your cable within the target work site area. Precipitation can wash away paint so flag markers are a better choice for identification in soil areas. On concrete type surfaces, paint is the better marking choice.
Keep Your Receiver Accurate and Working
Ensure that your receiver wand is always calibrated and always have a spare set of batteries on hand just in case. Don’t be afraid to touch the “self-check” button from time to time to ensure your receiver still working optimally.
Become Familiar with Your “Signal Gain”
To obtain the best locate signal possible, become familiar with your “signal gain” adjustment on your receiver wand. It is always best to first adjust the gain at the transmitter source to obtain the optimum locate signal (where you know it should be strong). In most cases, the cable will be visible to you within the man hole or hand hole structure.
Should I Use Null or Peak Mode on my Receiver Wand?
They are both very effective methods, just don’t get confused by which mode your receiver wand is actually in. Many missed locates are a direct result of mistaking the receiver to be in Peak mode when it was actually in Null mode.
Document Your Work!
On-site locates should always be substantiated by documentation to ensure that there is a full understanding between the locate requester (construction team) and the cable locate technician (asset owner) of the work area. Obtain signatures, provide sketches and take before and after photos of the worksite to ensure the full understanding between all involved parties.