CDM-50
& CDM-75
C A B L E D I S TA N C E M E T E R S
Operating & Instruction Manual
HDElectricCompany.com
INTRODUCTION
The Cable Distance Meter is a unique, handheld instrument, primarily used for the measureĀment of the height of overhead cables. The Cable Distance Meters measure up to 6 cables.
The CDM-50 model measures to a height of up to 50 feet (15m). The CDM-75 model has
an increased range of up to 75 feet (23m). The unit operates by transmitting an ultra-sonic
signal towards the wires, and measuring the time it takes to pick up the echo from that signal.
It automatically compensates for the fact that the speed of sound varies with temperature
by monitoring the ambient temperature using the internal temperature sensor. The display
continuously shows the ambient temperature reading. Because the temperature sensor
reacts relatively slowly to large temperature changes, it is necessary to wait up to 10 minutes
for the temperature reading to stabilize after taking the meter suddenly from a warm to
a cold environment before taking a measurement, e.g. taking the unit from inside a warm
vehicle to outside. Isolate the CDM from any hot surface such as sun warmed pavement
using a notebook or several sheets of paper.
Temperature Sensor
Stored Measurements
Read Stored Measurements
Make Measurement
Clear memory
Battery Compartment
(Side of Unit)
Cone
Transducer
Temp Indicator
Measurement Units
Height Measurement
ON Switch
CAL Mode
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