RLC500 Capacitor Bank Protection Relay – Strike Technologies
Access T&D supplies Strike Technologies numeric protection relays for medium- and high-voltage shunt capacitor banks and harmonic filter circuits, in Australia and beyond. The RLC500 is the current model.
RLC500 Capacitor & Filter Bank Protection Relay
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Product overview
NUMERIC CAPACITOR / FILTER PROTECTION RELAY
The RLC500 is a capacitor and filter bank protection relay that evolved from previous successful models on the foundation of years of continued development. It has quality embedded into every stage of its design and is manufactured to the strictest quality standards.
Combining state of the art hardware technology and software techniques the RLC500 provides the most convenient functionality in its sphere.
The RLC500 incorporates an impressive range of protection functions
• Thermal over-current
• Fundamental frequency over-voltage and over-current
• RMS over-current
• Fundamental frequency star point unbalance
• Fundamental frequency line current unbalance
• Fundamental frequency H-bridge configuration unbalance
• Fundamental earth fault current
• Fundamental frequency undercurrent
• Breaker Fail detection
• Capacitor bank re-switching
• Repetitive peak over-voltage
• Event tripping
Download: RLC500 specifications (PDF)
RLC500 technical specifications
| Parameter | RLC500 |
|---|---|
| Operating temperature | -10 to +55 °C |
| Humidity | Up to 93% RH |
| Auxiliary supply | Option 1: 100–230 VAC / 110–250 VDC. Option 2: 32–42 VAC / 24–60 VDC |
| Control outputs | K1 to K5, SPDT (N/O and N/C), 5 A at 264 VAC to 250 VDC |
| Watchdog output | K6, SPDT (N/O and N/C), 5 A at 264 VAC to 250 VDC |
| Signal outputs | SR1 to SR3, SPST N/O, 200 mA at 250 VAC or VDC |
| Digital inputs | Inputs 1 to 3: breaker on, reset, remote trip. Inputs 4 and 5 spare. 30–110 V AC/DC |
| Current inputs | 4 CT inputs, 1 A or 5 A. Burden ≤0.04 VA (1 A), ≤1 VA (5 A) |
| Communications | Front HMI; USB (1 × A, 1 × B); plug-in expansion modules: RS485, TCP/IP-RS485, Ethernet port-RS485 |
| Ingress protection | Front (HMI) IP51; rear (behind panel door) IP20 |
Source: Strike Technologies RLC500 specifications (PDF).
RLC500 compared with the RLC04-B
| RLC500 (current) | RLC04-B (legacy) | |
|---|---|---|
| Status | Released early 2018; replaced the RLC04 | Replaced by the RLC500 in 2018 |
| Current inputs | 4 CT inputs, 1 A or 5 A | 4 dual 1 A/5 A current measuring elements |
| Output relays | 5 control, 1 watchdog, 3 signal | 6 output relays (5 protection, 1 self-supervision) |
| Digital inputs | 5 inputs, 30–110 V AC/DC | 1 optically isolated input |
| Auxiliary supply | 100–230 VAC / 110–250 VDC, or 32–42 VAC / 24–60 VDC | 30–250 V AC/DC |
| Communications | USB; plug-in RS485, TCP/IP-RS485 and Ethernet-RS485 modules | RS232 or serial port |
| Records | Logs data on all important parameters; shows where in the bank the problem occurred | Trip history with time-stamping |
| Operator interface | Removable graphic HMI, English and German | LED status indication |
| Unbalance protection | Star point, line current and H-bridge unbalance as standard | Neutral unbalance with residual compensation and line unbalance; star and H configurations |
Sources: Strike Technologies RLC500 and RLC04 documentation. Ask us about upgrading an installed RLC04-B.
RLC500 frequently asked questions
What does the RLC500 protect?
Three-phase medium- and high-voltage shunt capacitor banks and harmonic filter circuits. The banks can be single star, double star, delta or H-bridge, with fused or unfused capacitors.
How does it detect a failed capacitor?
Banks are balanced in normal conditions. If one or more capacitor elements fail, the bank becomes unbalanced, the RLC500 senses this and can trip the associated circuit breaker.
Does it allow for natural unbalance in the bank?
Yes. The protection engineer can compensate for the bank’s natural unbalance, which allows closer settings and fewer spurious trips.
Does protection continue if the HMI is removed?
Yes. All protection functions stay active while the HMI is removed, hot connected or disconnected.
Can it show which phase has a problem?
Yes. It lets the user determine where in the capacitor bank phases the problem occurred, which reduces further downtime.
Is the RLC04-B still available?
The RLC04-B is a legacy model replaced by the RLC500 in 2018. Support, spares and manuals are available; contact us about upgrading.
Where is the RLC500 made?
Strike Technologies designs, manufactures and supports the RLC500 in South Africa.
RLC04-B Capacitor Bank Protection Relay (legacy model, discontinued)
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The RLC04-B is a legacy model and was replaced by the RLC500 in 2018. Support, spares and manuals are still available. Already using RLC04-B relays? Contact us about spares, support and upgrading to the RLC500.
Product overview
The RLC04-B protection relay provides comprehensive protection for the capacitive, inductive and resistive elements of three phase medium voltage and high voltage shunt capacitor banks and harmonic filter circuits. The capacitor banks consist of several individual capacitors in a series – parallel arrangement.
By only operating when absolutely necessary it prevents unnecessary trip outs thereby preventing unnecessary financial losses and other detrimental consequences. In addition, after a system fault or equipment failure, the RLC Protection Relay trips the associated circuit breaker timorously, to ensure maximum personnel safety, and to minimize further equipment and other consequential damage.
Protection Functions
- Repetitive peak overvoltage
- Thermal overcurrent
- Fundamental frequency overvoltage and overcurrent
- RMS overcurrent
- Fundamental frequency star point unbalance
- Fundamental frequency line current unbalance
- Fundamental frequency H-bridge configuration unbalance
- Fundamental earth fault current
- Fundamental frequency undercurrent
- Breaker Fail detection
- Capacitor bank re-switching
- Event tripping
Test functions
- Both on-line and user activated hardware diagnostic testing
Inputs/Output
Inputs
- 4 Dual Current Measuring Elements – Individually programmable for either 1A or 5A
- Optically isolated digital blocking input – User configurable for active low/active high
- Wide range AC/DC Auxiliary Power Supply (30 – 250V AC/DC)
Outputs
- 5 Trip/Alarm output relays (K1 to K5), programmable with regard to energisation and latching functionality, hardware configurable NO/NC contact form
- 1 Dedicated self-supervisory output relay (K6), hardware configurable NO/NC contact form
Enclosure
- Flush mount and 19” rack compatible
- Draw-out facility, with automatic shorting of CT input connections
User Interface
- 3 LED Status Indication: Healthy (Green); Alarm/Start (Yellow); Trip (Red)
- Alpha-numeric, backlit, Liquid Crystal Display (2 lines x 16 characters)
- Menu driven user interface with 5 button interactive keypad
Data Communications
- Two serial interfaces for programming and interrogation
- Remote communication by means of RS232 or RS485, either via a dedicated line or via a modem (PSTN or GSM).
- Both Strike protocol and Modbus RTU protocol co-reside in the product
Product Evolution Information
Released in early 2005, the RLC04-B replaces the earlier RLC Version 3 model. Although similar in overall functionality, there have been many major upgrades in hardware, specification, and operation to its predecessor.
“One relay fits all”. All of the features that were previously optional when ordering the relay, are now programmable via the set up menu. This means that there is only one version of this relay, which helps reduce your stockholding and offers the greatest flexibility should operating conditions change. The new application software addresses these new features.
The following are just some of the features that are new in the RLC04-B:
- Normal Mode or H-Bridge Mode is now programmable in the same unit
- 50Hz or 60Hz operation is now programmable
- 1A/5A CT selection is now programmable – no external wiring to change
- A second serial port (RS232) has been positioned on the front panel for ease of connection to a lap-top computer. This port is used for any communication with the unit, including Strike PC software or MODBUS, and in particular for firmware upgrades.
- The serial port on the rear of the unit is now RS232/RS485 programmable. This port can be used for Strike PC software or MODBUS.
- Both serial ports are separately programmable to baud rates of 2400 to 115200
- Greater accuracy of time and current measurements
- Much improved response time
- Time stamping of the trip history records and certain other status registers
- The digital input can be configured as one of three alternative functions; Breaker on sensing, an event input, or for remote reset
- Lost password recovery procedure avoids having to return the product to the factory for re-initialisation.
Download: RLC04-B operating manual (PDF)
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Supplier: Access TD Beyrouthi Family (ABN 21 418 290 162), PO Box 3768, Australia Fair QLD 4215, Australia. Contact us.