RX330 Earth Leakage Relay User Guide
Introduction
This user guide provides detailed information for the Mikro RX330 Earth Leakage Relay, a device designed for electrical safety and protection.
Features
- Built-in NFC for reading and setting parameters via a mobile app (Mikro RX app).
- Real-time monitoring of system conditions.
- Built-in self-test and soft recovery watchdog.
- Internal Relay Failure (IRF) alarm for system abnormalities.
- Time-stamped event record of power failures and setting changes (up to 120 events).
- Time-stamped record of up to 30 faults and 30 pickups.
- Selectable 50 or 60 Hz frequency.
- Selectable fundamental or true RMS measurement.
- Programmable Output Contacts.
- Detection of no connection to ZCT (Zero-Phase Current Transformer).
- Protected against nuisance tripping.
- Remote reset and test function.
- Incorporated fail-safe feature into trip contact.
- Self-reclosing feature.
Technical Data
| Auxiliary Supply | ||
| Supply Voltage | 198~265VAC | |
| Supply Frequency | 50 or 60Hz | |
| VA Rating | 3VA max | |
| Accuracy | ||
| Protection Thresholds | Ion Sensitivity | 20mA - 30.0A |
| Time At | INST - 10.0s | |
| Pre-fault | 10mA-24.0A | |
| Reset Hysteresis | 2% - 10% | |
| Time Delay | ±3% with a minimum 40ms | |
| Setting Ranges | ||
| (i) Earth-leakage Setting | Ion Sensitivity | 20mA - 30.0A |
| Time At | INST - 10.0s | |
| Pre-fault | 10mA-24.0A | |
| Reset Hysteresis | 2% - 10% | |
| (ii) Self Reclosing Setting | Number of Shots | OFF/1-30 |
| Dead Time | 1s-500s | |
| Persistent fault time | OFF/1s-500s | |
| Reclaim Time | OFF/1min - 500min | |
| Lockout Self Reset Time | OFF/1h-200h |
| Output Contacts | ||
| Rated Voltage | 250VAC | |
| Continuous Carry | 5A(Cosφ = 1.0) | |
| Expected Electrical Life | 105 operations | |
| Expected Mechanical Life | 5 x 106 operations | |
| Environmental Conditions | ||
| Temperature | -10°C to 55°C | |
| Humidity | 5% to 95% non-condensing | |
| Mechanical | ||
| Mounting | Panel mounting | |
| Dimension (mm) | 96(w) x 96(h) x 90(d) | |
| Enclosure Protection | IP54 at the panel, IP20 at the body | |
| Approximate Weight | 0.5kg |
Earth Leakage Protection Class: Type A
Zero-Phase Current Transformer: To operate with Mikro's ZCT series of current transformers.
Typical Application Diagram Description
The diagram illustrates the typical application of the RX330 relay. It shows connections for LOAD, CONTACTOR, and the relay itself. The relay receives auxiliary power via L and N terminals. Remote test and reset functions are available. The trip contacts (R1, R2, R3) and programmable outputs are shown. A Zero-Phase Current Transformer (ZCT) connects to terminals 1 and 2 for current measurement. A DANGER warning indicates potential electrical shock hazard.
Case Dimensions
The relay has the following dimensions:
- FRONT view: 90mm (width) x 96mm (height)
- SIDE view: 70mm (depth)
- PANEL CUTOUT: 91±0.5mm (width) x 91±0.5mm (height)
NFC Communication
The relay features built-in NFC (Near Field Communication) for convenient parameter reading and setting changes using a mobile app (Mikro RX app). Users can download the app from the App Store or Google Play. To connect, ensure the phone's NFC function is turned on and align the mobile phone's NFC antenna with the NFC logo on the relay's front panel. This action will direct the user to the appropriate app store.
System Operation and Push Button Controls
The relay features a digital display for measurement and parameter settings. Operation involves navigating through menus and settings using the push buttons.
Measurement Display
The display shows "Earth Leakage" with the measured leakage current (e.g., 0.000 A) and "Measurement" with the measured current (e.g., 10.00 A).
Menu Navigation
To enter the menu, press and hold the "MODE" button for 1 second. Use the "MODE" button to scroll through parameters, the "UP" or "DOWN" buttons to adjust values, and press "MODE" again to save settings.
Push Button Operations
- Trip Test: Press and hold the "TEST" button for 3.5 seconds.
- Trip Reset: Press the "RESET" button.
- Scroll Display: Press the "MODE" button.
- Enter Menu: Press and hold the "MODE" button for 1 second.
- Mode/Set/Save: Press the "UP" and "DOWN" buttons simultaneously.
- Adjust Setting: Press the "UP" or "DOWN" button.
- Display Off: Press and hold the "RESET" button for 10 seconds. The display will automatically switch off after 6 minutes of inactivity.
LED Indicator Status
The relay is equipped with LEDs to indicate operational status:
| LED | AUX | PRE.F | TRIP | RECLOSE | Status Description |
|---|---|---|---|---|---|
| 0 | 0 | 0 | 0 | No Auxilliary power supply | |
| 1 | 0 | 0 | 0 | Normal condition, no tripping | |
| 1 | X | 1 | X | X | Leakage pickup |
| 1 | X | B | X | X | Leakage tripped |
| 1 | X | X | B | X | ZCT connection fault alarm |
| 1 | B | X | X | X | Pre-fault alarm |
| 1 | X | X | X | B | Persistent/Transient fault lockout alarm |
Indicator Key: 1 = ON, 0 = OFF, B = Blinking, X = Don't care.
Alarm Codes: LFA - Leakage Fault Alarm, CFA - ZCT Connection Fault Alarm, PFA - Pre-fault Alarm, PLO - Persistent Fault Lockout Alarm / Transient Fault Lockout Alarm.
Note: Indicator status for R2/R3 may vary if their functions are set as Stc (Safety Contact) or IrF (Internal Relay Failure).
Link Element Configuration
The relay allows configuration of link elements, which can be set using hexadecimal values. These settings determine various alarm and status outputs.
| Digit1 | PLO | CFA | PFA | LFA | Description |
|---|---|---|---|---|---|
| 00 | 0 | 0 | 0 | 0 | |
| 01 | 0 | 0 | 0 | 1 | |
| 02 | 0 | 0 | 1 | 0 | |
| 03 | 0 | 0 | 1 | 1 | |
| 04 | 0 | 1 | 0 | 0 | |
| 05 | 0 | 1 | 0 | 1 | |
| 06 | 0 | 1 | 1 | 0 | |
| 07 | 0 | 1 | 1 | 1 | |
| 08 | 1 | 0 | 0 | 0 | |
| 09 | 1 | 0 | 0 | 1 | |
| 0A | 1 | 0 | 1 | 0 | |
| 0B | 1 | 0 | 1 | 1 | |
| 0C | 1 | 1 | 0 | 0 | |
| 0D | 1 | 1 | 0 | 1 | |
| 0E | 1 | 1 | 1 | 0 | |
| 0F | 1 | 1 | 1 | 1 |
Key: 0 = Off, 1 = On. These settings are user-configurable.
Self Reclosing Functionality
The RX330 relay includes a self-reclosing feature to automatically attempt to restore power after a trip event caused by earth leakage.
Terms and Descriptions
- Shots: Number of self-reclosing operations before lockout.
- Dead Time: The time delay after a trip before the first reclose attempt.
- Persistent Fault Time: The duration a fault must persist to trigger a lockout.
- Reclaim Time: The time required for the recloser to reset the shot count after a successful reclose.
- Lockout Self Reset Time: The time after which the relay automatically resets from a lockout state if no operator intervention occurs.
- Transient Fault Lockout: Lockout occurs when the number of self-reclosing operations matches the set number of shots.
- Persistent Fault Lockout: Lockout is initiated when tripping is caused by a persistent fault.
Self Reclosing Timing Diagrams
Diagram (a) Shots, Dead Time and Reclaim Time: This diagram illustrates the sequence of events. After an earth leakage trip, the trip safe contact opens. A dead time elapses, and the shots counter increments. If the fault clears, the relay resets. If the fault persists, after the reclaim time, the counter resets. This cycle repeats up to the specified number of shots before the relay enters a lockout state.
Diagram (b) Persistent Fault Monitoring Time: This diagram shows an earth leakage fault. The trip safe contact opens. After the dead time, if the fault remains present for the persistent fault time, the relay enters a lockout state.
