Power output contacts are used when the current rating requirements of thecontacts are high, for example, for controlling a breaker, such as energizing thebreaker trip and closing coils.The contacts used for external signalling, recording and indicating, the signaloutputs, need to adjust to smaller currents, but they can require a minimum current(burden) to ensure a guaranteed operation.The IED provides both power output and signal output contacts. To guaranteeproper operation, the type of the contacts used are chosen based on the operatingand reset time, continuous current rating, make and carry for short time, breakingrate and minimum connected burden. A combination of series or parallel contactscan also be used for special applications. When appropriate, a signal output canalso be used to energize an external trip relay, which in turn can be confiugred toenergize the breaker trip or close coils.Using an external trip relay can require an external trip circuitsupervision relay. It can also require wiring a separate trip relaycontact back to the IED for breaker failure protection function.All contacts are freely programmable, except the internal fault output IRF.3.10.1 Power output contactsPower output contacts are normally used for energizing the breaker closing coil andtrip coil, external high burden lockout or trip relays.3.10.1.1 Dual single-pole power outputs PO1 and PO2Dual (series-connected) single-pole (normally open/form A) power output contactsPO1 and PO2 are rated for continuous current of 8 A. The contacts are normallyused for closing circuit breakers and energizing high burden trip relays. They canbe arranged to trip the circuit breakers when the trip circuit supervision is notavailable or when external trip circuit supervision relay is provided.The power outputs are included in slot X100 of the power supply module.Section 3 1YHT530004D05 DBasic functions80 615 seriesTechnical Manual
