RF-IT & CE-IT Insulator Testers

• Move bolt to bolt to find contact
  
  
• Digital Meter
  
  
• Uses Radio Frequency to test effectiveness
  of above ground insulators
  
  
• Battery Operated
  
  
• Audible Beep
  
  
• Auto Shut-Off feature
  
  
• Use on structure regardless of CP

The Model RF-IT is a highly sensitive device used to test above ground pipeline insulators. The automatic RF-IT allows the operator to pinpoint the precise contact point. The RF-IT emits an audible beep and when the operator gets closer to the point of contact the unit starts beeping faster. A sliding scale LCD meter moves from left to right.

Theory of Operation
The RF-IT works using Radio Frequency. The Radio Frequency signal is applied to one side of a pipe by one of the two probes. The second probe then receives the high frequency signal. If the received signal is almost as strong as applied, the pipe is shorted.

The RF-IT has an internal band-pass filter which will filter out all the frequencies above and below 221kHz. This allows taking measurements on pipelines that are under cathodic protection or have other induced or impressed currents or signals. It is important to note that because the RF-IT uses Radio Frequency to measure the effectiveness of an insulator, the measurement results can not be displayed in Ohms.

• Senses external polarity
  
• Matches external polarity
  
• Sense external voltage
  
• Matches internal voltage reference with external voltage
  
• Sends charging voltage
  
• Senses flowing current throughout the testing cycle
  
• Gives result of test considering the above tested parameters
  
• Expected battery life exceeds 50 hours
• IMPORTANT NOTE: Do not use this instrument in an explosive environment.

The Model CE-IT Insulator Tester is fully automatic and highly sensitive electronic instrument designed to test the effectiveness of buried pipeline insulators. The CE-IT can also be used to determine isolation condition of pipelines in road crossing casings.

The Model CE-IT circuit automatically adjusts to the voltage polarity present on the underground piping system under test. A read out of the test results are displayed in English on the LCD meter. The entire testing procedure is complete in less than 30 seconds and an audible signal alerts the operator when the test cycle is completed. Although the Model CE-IT is equipped with power start switch, the instrument will automatically shut off in 10 minutes if not in use, to conserve batteries.

1. Substantially different ground voltage readings are evidenced on opposite sides of the insulator. The delta Vg is usually smaller or even in the opposite polarity (interference coupling) on the side of the insulator which is opposite from the protected segment of the pipe.
   
2. The percentage of current leakage that the joint will allow to flow through it is low (25 percent or less).
   
3. The voltage drop across the insulator is significant. (The voltage drop across an ineffective or shorted insulator would be negligible in the range of 10 millivolts or less).
   

1. First the CE-IT senses the polarity of the voltage at the test leads and then matches that polarity with the internal voltage in the instrument.
   
2. The CE-IT then senses the external voltage applied to the pipe and matches the internal voltage reference with the external voltage. (The maximum external voltage should not exceed 50 volts DC or 10 volts AC.)
   
3. After matching the external polarity and voltage, the CE-IT then measures the charging current applied to the protected side of the pipeline and senses the current flowing through the insulator throughout the testing cycle (about 20 seconds).
   
4. The CE-IT then displays the result of the completed test. A "Short" is indicated if the voltage drop across the insulator is between 12 and 10 millivolts or less, and/or the current leakage through the insulator is above 25 percent of the current applied to the protected pipe. An "Open" is indicated in the case of an open wire connection from the test station to the pipeline or the CE-IT test leads. A "Good" is indicated when the ground voltage readings (delta Vg) are smaller or of opposite polarity on the unprotected side of the pipeline, the current leakage through the insulator is less than 25 percent and the voltage drop across the insulator is greater than 10 to 12 millivolts.