489-P1-HI-A20-E

About the 489-P1-HI-A20-E

The Generator Management Relays from GE Multilin are best used in applications in which management and protection of synchronous and induction generators are required. The 489-P1-HI-A20-E model is just one of the models that can be used in these applications. The things that also differentiate this relay from others in the 489 Generator Management Relay series are the different code characters, for example, the P1 code on this relay indicates the phase current input which is one-ampere phase CT secondaries. The E at the end of this model indicates the display type on the front panel which is an enhanced display with a larger LCD screen. The remaining characters and appropriate codes can be found on page five of chapter two in the GEK-10649N 489 Generator Management Relay Instruction Manual. 

Trip and alarm protections are the main protection types available on the 489-P1-HI-A20-E relay. Some of the trip protection features are similar but have slight differences, for example, there are two neutral overvoltage and undervoltage types; one is a standard voltage type while the remaining two are neutral voltage types. The neutral overvoltage is described as fundamental while the neutral undervoltage is described as the third harmonic. 

Three main input types make up the 489-P1-HI-A20-E relay. These three types are analog, voltage, and digital inputs, all of which are vital to the operation of this device and have very specific characteristics. For example, the digital inputs, for which there are nine, can only be used in conjunction with dry contact connections. There is also a transistor output labeled as NPN which can be transferred to the assigned digital inputs as either a tachometer or counter.