The CHM Series of cable height meters, available from Megger , utilise ultrasonic techniques to determine the height of up to six overhead cables and wires.
Designed to address specific measuring requirements on cables up to 23 m, there are three cable height meter models available inteh CHM series, the CHM600 (C/N 659600) and CHM600E (C/N 659600E), which are designed primarily for power cable applications, and the CHM2000 which is designed for telecommunication applications.
These cable height meters emit short bursts of sound which originate from the cone shaped transmitter. The microprocessor in the instruments calculates the elapsed time for the bursts of sound to be reflected from the cable back to the instruments. The result can be displayed in either feet and inches or meters.
A temperature sensor mounted at the front of the instruments senses the actual air temperature in order to take the reading that is required before the final measurement can be displayed because the speed of sound varies at approximately 0.2 percent per degree Celsius. This air temperature information is sent to the microprocessor and incorporated into the algorithm and the distance is then displayed.
These cable height meters are capable of measuring the lowest cable, provided it is within range. Additionally, the spacing between the next five cables can be displayed.
Possible applications for use of these cable height meters include:
- telephone lines
- distribution lines
- transmission lines
- cable television (installers and contractors)
- street lights
- sag (lowest point to ground)
- separation between up to six cables
Key features and benefits of CHM Series cable height meters include:
- ease of use - simple, three button operation ensures fast, effective measurements with minimal operator training
- compact size - light weight and hand-held portability allows easy transport and multiple measurements
- inherently safe - no physical connection to cables or wires required to obtain measurement
- battery condition indicator - shows the battery warning symbol when the battery voltage falls to approximately 6 volts
- automatic power off - conserves battery power when idle after three minutes
- calibration and maintenance free operation - minimal down time
- pre-selectable measuring modes - will read in either meters or feet and inches for universal use.
- six cable measurement capability - handles almost any field application
- quicker measurement of cable height - saves time and money.