| 摘要 |
<p>A method and an apparatus for connecting a gage to an oil well pump power cable for transmitting pressure and temperature data to a surface recorder whereby the gage can be selectively disconnected when it is desired to test the insulation integrity of the pump power supply system, and selectively connected when the test is completed. The gage is connected to the neutral point of the three phase motor winding through a latching relay. A code transmitter generates a frequency coded signal on the power cable to a decoder which controls the relay. The same coded signal is utilized to open and close the relay contacts as desired.</p> |
