Home Services Methods Case Studies About RSI Publications




Electromagnetic Induction (Pipe and Cable Locator)

   RSI uses a simple EM induction hand-help pipe and cable locator to detect buried utilities and cables. This tool operates in 4 different modes: (1)Receiver only mode for detecting 60 cycle power (or harmonics thereof), (2)Direct Contact/Clamp mode where the transmitter hooks the positive lead directly to the pipe or cable while the negative lead is grounded, (3)Direct-coupled/ Inductive mode where an inductive clamp is place around the pipe or cable, or the transmitter placed over the inferred trend of the buried utility, and (4) Remote Beacon mode where a transponding beacon is placed on a fiberglass rodder and threaded through non-conductive pipes and traced from the surface using a receiving antenna.EMI utility locator

 

 

 Waterline markout

   Pipe and cable locators have a limited depth of investigation, especially when rebar is present. Under good circumstances, many manufacturers claim their locators can achieve up to 7 feet of investigative depth. From experience, they reliably go only 4 to 5 feet below grade.

    Above ground electrical sources, such as transformers, can interfere with the pipe and cable locator and cause false readings. Hence, for this and other reasons, survey data may be difficult to interpret. The effectiveness of tracing individual utility lines may be hampered by the proximity of other nearby utilities, especially if the soil surrounding them is conductive.