LOCATING COILS
Most models of the SW SERVICES Debris Cap™ are designed to accept a special 4" locating coil.
These coils (ScotchMark™ 4" Disc Marker), are manufactured by 3M, and are designed with built-in, discrete, passive, FM antennas which, when detected by a 3M locator, indicate their specific frequency. Discs come in standard utility color-codes, i.e. Blue, Yellow, Orange, Green, Red, each of which has it's own frequency.
3M locators come in models which only detect one of the frequencies (i.e. blue for water companies), or in modelswhich can detect all of the frequencies, and buried cable, pipes etc. as well.
These locating coils (discs) are not designed to work in cast iron valve boxes, but work quite well in concrete, clay, plastic etc., even if they have metal lids, at a depth of up to 4', and an accuracy of approximately 2" to dead-center.
Some models of the Debris Cap™ have three 'stand-off' brackets projecting from the bottom of the Cap main body, which are designed to hold one of these coils. Other models which do not come with these 'stand-offs', have slots in their underside into which a set can be installed if a coil is to be used. THERE IS NO CHARGE FOR THESE BRACKETS, but they must be ordered along with the locating coils if needed.
INSTALLATION
To install a locating coil (disc) into the stand-offs, simply rest the small ridge of the coil onto two of the stand-offs (figure 1), and 'pop' into place under the third stand-off, with the palm of your hand (figure 2).
