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CHAPTER 2: USING THE RTT ON SR SERIES RELAYS
THE SR489 GENERATOR MANAGEMENT RELAY
RTT DESKTOP TEST SET– INSTRUCTION MANUAL
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2.3
The SR489 Generator Management Relay
2.3.1
Overview
The SR489 Relay has 3-phase current inputs with CT burden less than 0.2 VA at rated load,
3 differential current inputs with the same CT burden and 3-phase voltage inputs with
greater than 500 KOHM VT burden. There are also 9 digital inputs designed for Dry contact
connection only, and 6 Form-C output relays. The SR489 Relay monitors up to 12 RTD
inputs, each RTD being field programmable as a 3-wire type of 100 Platinum, 100 Nickel
and 120 Nickel.
All features of RTT can be applied to the SR489 Relay. There are no unused terminals on
the RTT product cable. However a modification is required to the cable to fit to the SR489
terminals.
Modification of the Product Cable
For the wires related to contact inputs and RTDs (18 in total), cut the lugs off the wire, strip
wire to make them fit the SR489 terminals.
The lugs to be cut are: R1+, R1-, R1C, R2+, R2-, R2C, R3+, R3-, R3C, DIC, DI8, DI7, DI6, DI5,
DI4, DI3, DI2 and DI1.