Ground control unit for cable locating

Abstract

A system and method for selectively grounding each of a plurality of short-haul buried utility conveyances coupled to a common long-haul buried utility conveyance to enable a conveyance locating signal transmitted through the long-haul conveyance to travel from the long-haul utility conveyance to a selected short-haul utility conveyance. The system includes a first optical switch for selecting each of the plurality of short-haul utility conveyances to be grounded, where the first optical switch is adapted to receive an optical signal and selectively output the optical signal on one of a plurality of optical fibers; and a second optical switch coupled to each of the plurality of optical fibers for grounding each short-haul utility conveyance in response to the optical signal on a corresponding optical fiber.

1 . A method for selectively grounding each of a plurality of buried short-haul utility conveyances coupled to a common buried long-haul utility conveyance to enable a conveyance locating signal transmitted through the buried long-haul conveyance to travel from the buried long-haul utility conveyance to a selected buried short-haul utility conveyance, comprising:
 selecting a buried short-haul utility conveyance to be grounded among the plurality of buried short-haul utility conveyances by outputting an optical control signal;   selectively grounding each buried short-haul utility conveyance in response to the optical control signal.   
   
   
       2 . The method recited in  claim 1 , wherein the optical control signal is output from an optical switch coupled to an optical transmitter. 
   
   
       3 . The method recited in  claim 1 , wherein the optical control signal is output from an optical switch coupled to a cable locate tone transmitter. 
   
   
       4 . The method recited in  claim 1 , wherein the optical control signal is output from an optical switch remotely operated by DTMF control. 
   
   
       5 . The method recited in  claim 1 , wherein the optical control signal is output from an optical switch remotely operated by cellular control. 
   
   
       6 . The method recited in  claim 1 , wherein the optical control signal is output from an optical switch remotely operated over a network. 
   
   
       7 . The method recited in  claim 1 , wherein the optical control signal is output from an optical switch coupled to a cable locate transmitter, and is remotely operated over a network. 
   
   
       8 . The method recited in  claim 1 , wherein the optical control signal is output from a first optical switch coupled to an optical transmitter and a cable locate tone transmitter. 
   
   
       9 . A method for selectively grounding each of a plurality of buried short-haul utility conveyances coupled to a common buried long-haul utility conveyance to enable a conveyance locating signal transmitted through the buried long-haul conveyance to travel from the buried long-haul utility conveyance to a selected buried short-haul utility conveyance, comprising:
 selecting a buried short-haul utility conveyance to be grounded among the plurality of buried short-haul utility conveyances by outputting a control signal on one of a plurality of fibers; and   grounding each buried short-haul utility conveyance upon receipt of the control signal on a corresponding fiber.   
   
   
       10 . The method recited in  claim 9 , wherein the control signal is output by a switch remotely operated by DTMF control. 
   
   
       11 . The method recited in  claim 9 , wherein the control signal is output by a switch remotely operated by cellular control. 
   
   
       12 . The method recited in  claim 9 , wherein the control signal is output by a switch remotely operated over a network. 
   
   
       13 . The method recited in  claim 9 , wherein the control signal is output by a switch coupled to a cable locate transmitter, and is remotely operated over a network.