APTP Articles

Capacitor & Filter Bank Relay

Released in early 2018, the RLC500 replaces the earlier RLC04 model which is now superseded. It is used for capacitor and filter bank protection and now includes 3 communication protocols which are RS485, Ethernet and IEC61850.

The RLC500 is similar in overall functionality to RLC04, although there have been many major upgrades in hardware, specification, and operation to its predecessor. The RLC500 has quality embedded into every stage of its design and is manufactured to the strictest quality standards.

Comprehensive Protection

The RLC500 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. Each individual capacitor within a bank may be internally or externally fused or unfused. Several banks are constructed as a single star, double star, delta, or H-bridge configuration. 

In normal conditions, these banks are balanced, i.e. each leg draws the same current as near as practically possible. Should one or more of these capacitor elements fail, the system will become unbalanced and the RLC500 will sense it and can be used to trip any necessary circuit breakers. It allows the user to determine where the fault occurred in the bank phases, reducing downtime.

The combination of the protection functionalities in the RLC500 makes it a product of choice for any power compensation application. The RLC500 only operates when essential and thus prevents unnecessary trip-outs limiting financial losses and other detrimental consequences. It logs data on all important parameters.

The standard RLC500 has a firm set of protection features with modular communication capabilities allowing the customer larger flexibility with one product. 

A removable HMI with full graphics screen driven by a state-of-the-art configuration SW package offers greater flexibility when installing the RLC500.

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