ABB ARC GUARD SYSTEM™ - TVOC-2 7—FunctionalityArc monitorWith its modular concept, the Arc monitor is designed to fit all types and sizes of low- and medium-voltage switchgears.It is designed according to functional safety, and is SIL 2-certified according to IEC 61508 and IEC 62061 which puts full focus on reliability. This corresponds to performance level d according to EN ISO 13849-1. Safety functions are ex-clusively handled by hardware. In addition, the system, trip logs and user-interface are all microprocessor-monitored.The system can be configured to trip selected breakers, de-pending on which sensor that detects the light. The DIP-switches that take care of this function also handle settings like auto-reset and Current Sensing Units (see pages 12-13 for more details).Energy is stored in the unit for operation up to 0.2 s if the supply voltage fails. This is sufficient to close the tripping circuit even if voltage disappears at a short-circuit fault.Note: The circuit breaker still needs a back-up energy source for its tripping circuit. ConnectionsAll connections can be accessed from the front of the Arc Guard System™. Pluggable terminal blocks allow electrical wiring before mounting TVOC-2 into the cabinet. The solid state tripping contacts are type IGBT, which guar-antees fast and reliable tripping. More details can be found on page 8, technical data.HMI (Human Machine Interface)• Handles settings with key-pad and full text display• Holds error log and trip information after power loss• Error log and trip log include time/date stamp from a real-time clock• TVOC-2 can handle two separate HMIs (cabinet door and on product)• Three-meter cable included• COM Module available using Modbus RTUSensor & sensor modules• Fiber-optic sensors not affected by electrical noise• Pre-calibrated sensors remove need for manual configuration• Up to 30 detectors can be connectedCurrent Sensing Unit (optional)The Current Sensing Unit (CSU) is an accessory needed only in those few specific applications where strong light is expected on a regular basis. CSUs are connected with an optical fiber using light as signal for normal current. If this was removed by accident, the system would treat it as an over-current and trip if an arc flash is seen of reliability reasons. Adding a CSU will result in an additional operating time depending on the size of the over-current and the number of phases measured.Arc monitor3 IGBT solid state tripping contacts2 change-over trip signal relays1 change-over self supervision alarm relay (IRF)2 current sensing unit inputs1 current sensing unit outputMounting alternativesDIN-railWall mountingOptical detector inputs1-10 Main unit X1 1-10 Extension module X21-10 Extension module X3HMICan be mounted on doorIP54Additional HMI possibleUser-friendly start up menuCOM Module version available
