Switchgear / XDP

Applications

-Quality control of the insulators during installation or underground network repair
-Follow-up of the ageing process of the critical components’ insulation
-Safety control prior to work conducted under charge

The XDP checks if a designated site to carry out underground workloads under high voltage is safe or not. The user sweeps the capacitive sensor over the joints of the cables he wants to inspect and if any problems are detected, the XDP then informs him of the shape of the partial discharge signals along with the peak value. What’s more, the instrument allows, in “analysis” mode, to proceed with a comparative signal inspection with the help of its own database, which encompasses ten reference signatures in order to establish a correspondence with the four nearest signatures to the one obtained on the joint. 

It is also possible to record the discharge measurement graphically and in audio form along with the date and the hour of the reading. The user may also listen to his recording on the premises. The recorded measurements remain stored in memory even when the XDP is shut off. This allows the transfer of these recordings to a computer upon return from the worksite. The ten reference signatures can be listened to anytime and can be replaced to enhance the internal database of the instrument.

Advantages of the XDP

-Verification of the joints under normal charge of the electric network
-Use of the surface sensor, which does not require direct access to the cable’s voltage
-Progressive analysis of the database
-Keeps the readings in memory, with the date and the hour
-Transfers the collected data stored in a computer to ensure the follow-up of -the measurements
-Communicates the results to an expert via a computer connected to the Internet
-Water-proof and rugged for work site applications

Operation

The partial discharges are tiny electric arcs, which occur whenever a flaw appears inside the insulating equipment. These partial discharges prompt an abrupt variation of the magnetic field surrounding the cable where they occur, a variation that one can come and read in a secure way with the insulated sensor capacitor used by the XDP. The capacitive sensor is smooth and can be hand-fitted to all the diameters of cables and joints. An insulated rod allows the user to proceed with the sensors sweeping at a safe distance from the cable.