iZAZ350 - Description

Application area

iZAZ350 units represent a series of digital, multi-functional protection and control devices for electric power systems, featuring high computation performance, data transmission capability and up to 32 inputs for measured parameters. Distinguished by high accuracy and functional reliability, these devices can be operated in automatic control systems as comprehensive protections for renewable energy connection bays (photovoltaic farms, wind farms, biogas plants), for MV bays of various types (power supplying, busbar connectors, output lines, transformers, motors, measuring instruments, etc.), for HV bays and for low power generators. With appropriate hardware and software configuration the units offer automatic functions such as automatic underfrequency load shedding (UFLS), Automatic Reclosing (AR), undervoltage load shedding (UVLS), busbar protection (BP), Automatic Transfer Switch (ATS), Return Transfer Switch (RTS), Planned Transfer Switch (PTS) and local breaker failure (BF), as well as the tap changer voltage regulator function (TRU) for transformer voltage control and automatic generator synchronization (ASG).

The iZAZ350 unit can also be applied as a five-zone distance protection with polygonal or MHO impedance characteristics, provided with single-phase Automatic Reclosing, teleprotection channel and reverse current functions, fault location function and power swing blocking function. The iZAZ350 unit can also perform the function of a differential protection for medium and high voltage lines, implemented as two half-sets with a dedicated fibre optic link.

Beside the protection and automatic control functions the units are suitable for measurements, data recording, emergency control and signalization. Communication with the unit is possible through RS-485 serial ports (with optical fibre version as an option), the LAN port via a copper or optical fibre cable as well as the USB port on the operator's panel. Optionally, the communication capabilities can be extended with additional PRP-A and PRP-B Ethernet ports for redundant IEC 61850 communication or with CAN-BUS ports. The modular design allows the hardware configuration to be adjusted to the requirements of the protected facility. A 3.2" colour touch display clearly presents the mimic diagram of the bay along with necessary measurements and supplementary information. A larger operator's panel of 7” (from the iZAZ400 unit) can be ordered as an option. The field programmable operating logic, edited graphically, enables clear implementation of various applications, both standard and application-specific, considering the requirements of a given facility. The bay controller enables control of the circuit breaker and switching devices while maintaining the required functional interlocks.

The universal hardware and software design allows the device to be reconfigured and adjusted to various objects simply and intuitively. The application database developed by the manufacturer provides ready default solutions. The configuration can also be amended to suit the specific properties of the protected facility and the needs of the user. Amendments may include supplementing the implemented protection or automatic functions and altering the logic and timing relations (among others the control of signal LEDs on the panel, signalization on the display, control of the signalling relays and the manner of emergency control).

The iZAZ350 relay was adapted to work with the flash sensor for arc protection.

Recorders

The unit is provided with three different recorders that enable analysis of phenomena occurring in the protected facility.

Events recorder – the basic recorder of states, stored in the chronological log of events with the resolution of 1 ms. Circular memory buffer with the capacity of 3000 events. The recorded data comprise pick-up, drop-off and tripping of protections as well as changes in statuses of binary inputs, automatic functions and other events originated from the internal logic. Each event is subject to individual edition of names and comments, thus it is possible to adapt the system to any specific application, which considerably facilitates analysis of disturbances by the user.

Actuation recorder – enables quantitative analysis of disturbances. Besides the time of each disturbance the record comprises information about limit values of the signals that were measured from the moment of pick-up until the drop-off of the function after it has been tripped. Types and amounts of recorded data depend on the nature of each specific function, e.g. for an overcurrent protection these are the disturbance duration and the maximum current value during that time. The actuation recorder enables rapid evaluation of the event and provides information about the criteria parameters associated with the disturbance. It is also conducive to verification of the settings. For a typical record that comprises three analog parameters (e.g. the maximum current or voltage) the internal circular buffer enables storage of up to 200 records.

Disturbance recorder – the set of data recorders for analog and binary waveforms with the function of a criterion-dependent data recorder that enables complete analysis of disturbance phenomena. The unit enables implementation of up to two totally independently adjustable recorders. The function of a criterion-dependent data recorder offers the possibility to record any of the criteria parameters available within the unit (both analog and binary ones). The standard pre-run, rundown and maximum recording time settings enable proper configuration of the recording window for the phenomenon of interest. To optimize recording of long-lasting, slowly varying processes, the sampling frequency can be reduced, with the option to control the recording decimation by a selected binary signal (e.g. an open circuit breaker, the startup state, etc.). The internal buffer capacity depends on the number of activated recorders, the number of programmed analog and binary channels and the maximum duration of a single recording. For a single recorder with 8 analog and 64 binary channels a file of 1000 s can be recorded.