The Equipment; High Voltage Unit; Tracer - Danfoss DEVItector II V2 User Manual

User Guide

4. The equipment

The DEVItector™ II V2 equipment comprises:
1. A high voltage unit (HVU) with a built-in 1,8 kHz
transmitter.
2. A battery-driven Magnetic tracer on crutch.
3. A battery-driven Magnetic tracer - Hand held.
The devices are shown in Fig. 3.

High Voltage Unit

The high voltage unit is used for creating a short
circuit at the fault location by applying a high voltage
between two conductors thus burning the polymer
insulation into a so called carbon bridge at the fault
location.
The HVU also acts as a transmitter exposing the
heating cable to a 1,8 kHz square voltage. This signal
generates a magnetic field around the conductors
from the burner terminals along the cable to the fault
location.
Fig. 3: Photo of High Voltage Unit (left), the Magnetic tracer on crutch (mid) and the Magnetic tracer -
Hand held (right).
Note: The photos are not to scale.
BC421332622232en-010101
DEVItector™ II V2

Tracer

The tracer is a magnetic sensor which is an open
transformer comprising a ferromagnetic yoke and
a pickup coil. Thus the 1,8 kHz magnetic flux from
the heating cable is converted into an amplitude
modulated voltage. This signal is also converted into
an acoustical signal and output to a set of earphones.
A maximum tracer signal indicates the closest
distance to a cable segment. However, this case may
be modified due to the effect of closely neighboring
cable segments. The tracer has a gain and volume
control which allows you to adjust the meter or
volume level to fit the actual depth of the cable.
2022.07 | FEC | ©Danfoss | 5