Eaton Cooper Power NR Series Maintenance Instructions Manual

Contents

Product informationIntroductionService Information MN230001EN covers the maintenanceinstructions for Eaton's Cooper Power™ series Type NRelectrically-operated, single-phase, oil switches. Thisincludes their general description, operating principles andinstructions for periodic inspection and shop repairs. Serviceparts lists, keyed to exploded-view drawings of the switch,are included at the back of the manual.Type NR oil switches are single-phase, electrically-operatedwith a quick-close, quick-open mechanism which alsoprovides the switch with close-and-latch capability.The switches are electrically operated. The standard actuatorcan be operated by any three-wire control device employinga set of SPDT contacts.Read this manual firstRead and understand the contents of this manual and followall locally approved procedures and safety practices beforeinstalling or operating this equipment.Additional informationThese instructions do not claim to cover all details orvariations in the equipment, procedures, or processdescribed, nor to provide directions for meeting everypossible contingency during installation, operation, ormaintenance. For additional information, contact your Eatonrepresentative.Acceptance and initial inspectionEach Type NR oil switch is completely assembled, tested,and inspected at the factory. It is carefully calibrated,adjusted and in good condition when accepted by thecarrier for shipment.Upon receipt, inspect the carton for signs of damage.Unpack the switch and inspect it thoroughly for damageincurred during shipment. If damage is discovered, file aclaim with the carrier immediately.Handling and storageBe careful during handling and storage of the switch to min-imize the possibility of damage. If the switch is to be storedfor any length of time prior to installation, provide a clean,dry storage area.StandardsType NR oil switches are designed and tested in accordancewith IEEE Std C37.66™-2005 standard.Quality standardsISO 9001 certified quality management systemDescription of operationWith the main switch contacts closed, energizing theopening circuit will operate the actuator motor to releasea toggle which allows the preloaded opening springs tosnap open the switch contacts and load the closing spring.It also drives the cam to position the selector switch fora closing operation and interrupts the opening circuit tostop the motor. The opening circuit must remain energizedfor at least 4.0 seconds for the actuator to perform thesefunctions.With the main switch contacts open, energizing theclosing circuit will operate the actuator motor to allow thepreloaded closing spring to snap closed the switch contactsand load the opening spring. It also drives the cam toposition the selector switch for an opening operation andinterrupts the closing circuit to stop the motor. The closingcircuit must remain energized for at least 0.5 seconds forthe actuator to perform these functions.A holding switch accessory installation in the actuatorreduces to one second the minimum time the control mustbe energized to effect an opening or closing operation.1TYPE NR OIL SWITCH MAINTENANCE INSTRUCTIONS MN230001EN February 2016