The PD monitoring system PD GUARD from HV Technologies is especially developed for continuous partial discharge monitoring of high-voltage equipment, like generators, motors and power transformers.
The decoupling of the PD pulses will be done by Capacitive Couplers PDDC-24 (rotating machines, mounted near to the terminals) or by Measuring Impedance LDM-6 (transformers, mounted to the bushing tap adaptors). One superimposed signal of each phase with information of PD signal and voltage signal will be transmitted to the PD GUARD. Up to four phases (e.g. three phases and neutral phase at a rotating machine) can be monitored with one PD GUARD.
The PD GUARD can be installed close to the monitoring object. The stable, compact and lightweight construction and the degree of enclosure protection IP65 allow an installation in all industrial surroundings (wall mounting in any position, no mechanical moving parts inside - no hard disks, no fans), only a normal power socket is necessary. The system is able to trigger to phase signal, external trigger or internal mains signal. One gating channel is available for suppression of external noises.
The stored PD information can be further evaluated by the acquisition and evaluation software, which features graphical displays of all channels, e.g. the phase resolved PD pattern, PD frequency and a charge trend.Each PD GUARD is addressed with an IP-identifier for communication with the data server. The IP-addresses are necessary for identification of the data streams coming from and the to-do tasks coming to each PD GUARD, controlled by the data acquisition server. Each PD GUARD can be separately configured for each monitoring channel by the monitoring software, which also allows an easy alarm and filter setting. The alarm output can be adjusted for visualization in the monitoring software and for email message. Alarm criteria are PD level and PD repetition rate (adjustable).