The aim of recording is to identify emerging disturbances and interferences. A high level of them may cause failure states. A failure in a power system may have unexpected effects and their removal may be expensive. Disturbance recorders enable to detect and analyze irregularities appropriately early. These devices and resistant to harsh environmental conditions in power substations.
Disturbances are signals measured with high frequency. The SMT-102/103 device is able to record them with the frequency of 2 500 000 samples per second. The speed of voltage fluctuations triggering an oscillogram record is up to 2000 kV/µs. Basing on a knowledge database and identified premises, appropriate alarms and notifications are generated, associated with prompts and explanations for maintenance and dispatching staffs.
The SO-52v11-eMR device is designed to record disturbances in low, medium and high voltage power switchgear bays.
Depending on the number of signals to be recorded, individual recorders can be connected into a network, creating a hardware layer of a substation, distributed interference recording and analysis system. Data are collected on the SD card in COMTRADE files and sent to the supervisory system.
In the master system, they are processed by specialized software in order to identify the causes of failures, locate failures or assess the condition of the network.
Standardized communication protocols of the recorder allow for cooperation with data readout and analysis systems from various manufacturers.
As a standard, the SO-52v11-eMR recorder is equipped with the following modules:
The modules are linked and powered by two internal communication buses. The design of the recorder modules enables their replacement under voltage, without the need to disconnect the power supply.
The central unit module performs transmission via the Ethernet network channel with external communication devices or other systems using the DNP 3.0, Modbus, IEC61850, TFTP, FTP, http, Telnet protocols or other protocols agreed with the manufacturer. The MPL-416w.014 module is a voltage-current measuring module. It has 4 voltage measurement inputs with a rated value of 100V and 4 current inputs measuring in the 1A, 5A, 20A and 100A ranges. The MWS-501-H w.221 binary input module has 32 independent, galvanically separated inputs. The rated voltage of the channel is 220V DC. The module has input voltage hysteresis. The power supply module supplies all the device modules with the required voltages.
The MPL module measures currents and voltages continuously and synchronously with appropriate precision. When the recording trigger criterion is met, fast-changing, sampled waveforms of analog input signals, binary signals and slow-changing waveforms of calculated network parameters, such as power, voltage or current unbalance components are recorded. All records are made with registration, advance, follow-up and post-trigger times. Two types of recording runs have been implemented in the recorder, fast and slow-changing.
In order to ensure the widest possible field of recorder applications, the device has been equipped with several types of recording triggers:
The SO-52v11-eMR-1T/2T recorder is designed to record disturbances in the fields of low, medium and high voltage power switchgears. The recorder measures the quantities and parameters required to assess the size of disturbances, including "transients" disorders. Single recorders can be connected to the network, creating the hardware layer of the substation, distributed continuous disturbance monitoring system.
After collecting the data, they are sent to the supervisory system. There, they are processed and presented by a specialized system for disturbance analysis based on the SYNDIS system.
The recorder can be made with one measuring input module (version
SO-52v11-eMR-1T) or with two modules (version SO-52v11-eMR-2T). The single-module version is used to record the parameters of 4 voltages and 4 currents in one measurement field of the power grid. The version with two modules allows simultaneous supervision at two points of the power network. Each module is individually configured, so it is possible to measure at different voltage and current levels. For example, on the HV and LV side of a transformer or on a bus and an outlet bay in a power switchboard.
Standardized communication protocols of the recorder allow for cooperation with data reading and analysis systems from various manufacturers.
As standard, the recorder (SO-52v11-eMR-1T) is equipped with the following modules:
The device is equipped with the function of recording events such as dips, interruptions, swells, inrush currents, overruns and user-defined events. At the moment of meeting the recording triggering criterion, voltage and current signal waveforms are recorded with a defined advance and continuation time.
The recorder checks on an ongoing basis the compliance of the values of each input voltage and current with the threshold values set during the configuration. Each breach of the threshold value for a dip, decay, voltage rise, rapid voltage change or surge current causes the recording of the input samples and/or the calculated half-period RMS values of voltage and current to be triggered. The device has three types of recording passes:
The device has several types of recording triggering criteria:
The conditions of the thresholds and the rate of their rise are configured in the pConfig program. 
The SO-52v11-R disturbance recorder performs records of disturbance and operation courses in switchings substation bays of all voltage levels. Depending on the number of signals which are to be recorded, single recorders may be connected into a network, creating the hardware aspect of a substation distributed system for disturbance recording and analyzing. Gathered data is sent to a superior system and processed by specialized software in order to identify causes of failures.
The modules and connected and supplied by the internal LVDS bus. In its maximal configuration, the recorder may be equipped with 4 modules of the MWS-201w.200 type and a redundant MZA-210 power supply module.
Basic functions of the recorder are performed by the MPA-351-1R measurement-communication module. It continuously measures currents and voltages. If conditions for recording initialization are met, courses and analog and binary signals are recorded with appropriate advance and delay times. Parameters of recording initialization and its duration time are defined during configuration of recorder parameters.
The communication-measurement module realizes also transmission with external communication devices and other systems using the MODBUS, DNP 3.0, IEC1850, TFTP and other protocols, defined while designing a given application.
An outstandingly interesting device is our specialized measurement transducer, SMT-101, equipped with a set of measurement probes, designed for bushing monitoring. The implementation of this device has given us extraordinary "power" experience when we have successfully recorded courses of discharges and short-circuits on an 110 kV line in the Zakład Remontowy Energetyki [Power Renovation Company] in Czerwonak.
The transducer records connection and storm overvoltages on the primary and secondary sides of a transformer. It detects dynamic changes of bushing capacities and long-term changes, which indicate a rapid or slow degradation of dielectric layers. Measurements are transmitted to the SYNDIS ES system, our expert software, which is able to determine the change of the bushing loss rate. Appropriate messages and notifications are generated on the basis of change trends.
We believe, that systematic statistic of recorded atmospheric overvoltages, including their measured values, provides valuable information about lightning protection on a substation.
During exploitation of the transducer it has appeared to record also voltage disturbances connected with failures in a power system as well! Such records may be applied for additional verification of operation of disturbances recorders and some protection devices.
The SMT-102/103 module has a dedicated microprocessor-based measuring system with a recording function and is designed for the monitoring of bushings. The system supervises up to 6 bushings, which are equipped with network and block power transformers. The device can cooperate with transformer monitoring systems, SSiN substation systems or function independently as a substation automation device.
The SMT-102-Z recorder consists of a power supply, a measuring module and a binary output module, eg MSS-216. Then, it is possible to derive warning and alarm signals. The SMT-103 recorder is equipped only with the SMT-102 measuring module with the MZA-101-15 power supply, without the binary outputs module.
Signals from CPT-00x probes, located in the measuring sockets of the bushing insulators, are fed to the inputs of the measuring lines. Monitoring can cover both the upper and lower voltage side of the transformer.
The device can be mounted on or on the surface. The recorder communicates with independent, external diagnostic software, e.g. with the SYNDIS ES or SYNDIS ESB monitoring system.