Protection Functions

The protective functions of the REF610 with their IEC symbols and IEEE device numbers are shown in the table below.

The protection functions, their IEC symbols and IEEE device numbers are shown in the table below:

Outputs

The relay is equipped with

* three power output contacts PO1. PO2 and PO3

* two signal output contacts SO1 and SO2

* three optional signal output contacts SO3. SO4 and SO5

Switch group SGR1…. .8 is used to route internal signals from the protection stage, external trip signals and signals from the automatic reclosing function to the required signal or power output contacts.

The minimum pulse length can be configured as 40 or 80 ms and the power output contacts can be configured as latching.

Trouble Logger

The relay has a built-in disturbance logger that records the instantaneous measured value or the RMS curve of the measured signal.

and up to eight user-selectable digital signals: digital input signals and internal signals from the protection stage.

Any digital signal can be set to trigger the recorder on the falling or rising edge.

Front Panel

The relay front panel consists of

* 2 × 16 character alphanumeric LCD with backlight and automatic contrast control Controls

* Three LED indicators (green, yellow, red) with fixed functions

* Eight programmable LED indicators (red)

* HMI button section with four arrow buttons as well as clear/cancel and enter buttons for navigating through the navigation bar.

HMI button section with four arrow buttons as well as clear/cancel and input buttons for navigating through the menu structure and adjusting setting values

* Optically isolated serial communication port with LED indicators.

HMI passwords are divided into two levels: the main HMI setup password for all settings and the HMI communication password for communication settings only.

HMI passwords can be used to protect all user changeable values from being changed by unauthorized personnel.

Both the HMI setup password and the HMI communication password are inactive and are not required to change parameter values until the default HMI password is changed.

Non-Volatile Memory

The relay can be configured to store various data in non-volatile memory, even in the event of loss of auxiliary voltage (as long as the battery is inserted and charged), the

The non-volatile memory retains data even in the event of loss of auxiliary voltage (as long as the battery is inserted and charged). Operation indication messages and LEDs, interference logger data,

The EEPROM does not require a battery backup.

Self-Monitoring

The relay’s self-monitoring system manages fault conditions during operation and notifies the user of existing faults.

There are two types of fault indications

Internal Relay Fault (IRF) indication and warning.

When the self-monitoring system detects a permanent internal relay fault and prevents the relay from operating, the green LED (Ready) will flash.

At the same time, the normally open IRF contact (also known as the IRF relay) will open and a fault code will be displayed on the LCD. The fault code is numeric and identifies the type of fault.

Time Synchronization

Time synchronization of the relay real-time clock can be achieved in two different ways

Serial communication via communication protocol or via digital input.

When time synchronization is achieved via serial communication, the time is written directly to the relay’s real-time clock.

Any digital input can be configured for time synchronization and used for minute pulse or second pulse synchronization.

The synchronization pulse is automatically selected, depending on the time range in which the pulse occurs.

Two pulses need to be detected within an acceptable time range before the relay activates pulse synchronization.

Conversely, if the synchronization pulse disappears, the relay requires the equivalent of four pulse time ranges to de-synchronize the pulse.

The time must be set manually once via serial communication or the HMI.

When setting the time via serial communication and using minute pulse synchronization, only the year-month-day-hour-minute is written to the relay’s real-time clock;

When using seconds pulse synchronization, only year-month-day-hour-minute-second is written. The relay’s real-time clock will round to the nearest whole second or whole minute.

depending on whether seconds pulse synchronization or minutes pulse synchronization is used. When setting the time via the HMI, the entire time will be written to the relay’s real-time clock.

If the difference between the synchronization pulse and the relay’s real-time clock for seconds pulses exceeds ±0.05 seconds, or for minutes pulses exceeds ±2 seconds, the synchronization pulse will be rejected.

Time synchronization is always triggered on the rising edge of the digital input signal. The time is adjusted by accelerating or decelerating the relay clock.

In this way, the clock neither stops nor jumps suddenly during time adjustment.

Typical accuracy of time synchronization via digital inputs is ± 2.5 ms for second pulse synchronization and ± 5 ms for minute pulse synchronization.