RSK - 80

The relay annunciator unit RSK 80 finds application in electric powerand industrial plants for monitoring the operation of protective relays; in turbine protection for monitoring the control values (oil flow monitoring, cooling water flow monitoring, temperature incerease monitoring, oil pressure monitoring, etc.) and in switch gears for monitoring the compressed air pressure and the like. The RSK 80 unit contains eight auxiliary relays and serves to furnish audible and light information on contact closure of protective relays with capability of selecting the signal type for remote annunciation by means ofajumperon the unit front plate.

The RSK 80 unit announces the operation of protective relay contacts in the following method: When the protection contact has been operated, the' corresponding relay is energized and its contacts are closed; one set of these contacts turns on the corresponding signal lamp which lights with permanent intensity, ana tne otner set of contacts gives a signal for remote annunciation to the terminal 13 oftheterminal block K2. The remote annunciation signal can be selected between fast blinking and slow blinking light by means of a jumper arranged on the unit front plate under the cover. Fast blinking light is fed to the terminal 14 of the terminal block K2 which is wired to the bus "a", and slow blinking light to the terminal 15 of the terminal block K2 wired to the bus "b";. By inserting a jumper into "a" or "b", it is possible to selecte between fast and slow blinking light for remote annunciation of associated protection contact. The remaining set of contacts serves to keep the relay energized until a resetting command is given via the terminal 8 of the terminal block K1. If the permanent light lamp continues to light after resetting command, it means the protection contact is still closed due to a persisting failure. After removing the persisting failure it is necessary to issue a repeated resetting command and the permanent light will go off. If the protection signal was only temporary, i.e. only a short duration contact closure of the protection occured, the permanent light will go off after first resetting command.
The protection contact simultaneously energizes the alarm relay ATP-10 which is to be wired to the terminal 7 of the terminal block K1. Lamp test is performed by apolying positive pole of the auxiliary voltage source to the terminal 24 of the terminal block K2.

The RSK 80 unit has a wide scope of apolication. It does not require any inspection or maintenance; it is not susceptible to vibrations and mounting position. It is housed into a standard housing for surface mounting, see fig. 2. The employed auxiliary relays are high quality relays offering a reliable performance and long life. Printed circuit board wiring technique has been applied, and easily accessible fast acting fuses arranged on the printed circuit board under the unit cover are incorporated for the protection. External connections of the unit are made on two terminal blocks K1 and K2 containing each 12 terminals.