Eaton ATC-900 Instruction Booklet

Also see for ATC-900: Operation and maintenance manual Manual Operation and maintenance manual Instruction booklet Operation and maintenance manual

Contents

IB140036EN For more information visit: www.eaton.comInstruction BookletEffective: October 2014 Page 21O&M Manual for 40-1200A (480/600 Vac) ATC-900 3-Position,Open/Closed Transition Contactor Based Transfer Switch10. Once the manual operation is complete and automatic opera-tion is desired, connect the sources of power.11. Check for 120 Vac at J7-2 to J7-1 if Source 1 is available.12. Check for 120 Vac at J7-4 to J7-3 if Source 2 is available.13. Insert the J7 connector into the controller.14. Follow the testing procedure in Section 6 to ensure properautomatic operation.5.3 Automatic TransferThe operating sequence of an ATS is dictated by the switch'sstandard features and selected options. Operation of an ATSduring Source 1 power source failure and Source 1 power sourcerestoration will be described here with only standard optionsincluded on the switch. Additional options, as described in Sec-tion 3.5.2, can change sequences and timing, depending uponthe options selected. It is strongly suggested that you becomefamiliar with additional options selected with the particular ATSand their effect on the normal operation of an ATS.5.3.1 Source 1 Power Source FailureStandard Source 1 power source failure is defined as a reductionor loss of voltage. If this occurs, the sequence of operation is asfollows.1. Failure of Source 1 is detected by the controller intelligence.2. When the controller detects a failure, the engine contactsclose (after delay if programmed) and start the engine-drivengenerator.3. When the Source 2 voltage reaches its operation rating, theK2 and K4 relays inside ATC-900 controller operate to starttransfer operation to Source 2. This operating sequencecauses the contactor to open Source 1 and close onSource 2.4. The load is now transferred to the Source 2 power source.5.3.2 Source 1 Power Source Restoration1. A return to the Source 1 power source begins when the volt-age in all phases of a 3-phase sensing unit, or phase-to-phase in a single sensing unit, is restored to a preset value.2. At the preset voltage, K1 and K3 relays inside ATC-900 con-troller operate to start transfer operation to Source 1.3. During this sequence, the contactor opens Source 2 andcloses on Source 1.4. Simultaneously, the engine cool-down timer initiates the shutdown of the engine driven generator.5. Transfer of the load back to the Source 1 power source isnow complete.Section 6: Testing and Problem Solving6.1 TestingAfter the ATS equipment is initially installed or during plannedoutages, the installation should be tested to ensure that all equip-ment operates properly. This attention to detail will help avoidunexpected malfunctions. Mechanical and/or electrical testsshould be performed as described in this section.The frequency of subsequent testing should be based on recom-mendations of the Genset manufacturer. Use the test pushbut-ton on the ATC-900 controller to check the electrical operation ofthe switch.WARNINGHIGH VOLTAGES ASSOCIATED WITH OPERATIONAL TRANSFERSWITCH EQUIPMENT PRESENT A SHOCK HAZARD THAT CANCAUSE SEVERE PERSONAL INJURY OR DEATH. USE EXTREMECAUTION TO AVOID TOUCHING ELECTRICAL CONNECTIONSWHENEVER INSPECTING OR TESTING THE EQUIPMENT.IN ADDITION, IMPROPER OPERATION OF THE GENERATOR SETPRESENTS A HAZARD THAT CAN CAUSE SEVERE PERSONALINJURY OR DEATH. OBSERVE ALL SAFETY PRECAUTIONS IN YOURGENERATOR SET OPERATIONS AND INSTALLATION MANUALS.6.1.1 Mechanical and/or Electrical TestingNOTICESINCE FEATURE 4 (TIME DELAY ENGINE COOL-OFF), ASDESCRIBED IN SECTION 3, IS A STANDARD FEATURE, AN ENGINESTART SIGNAL WILL BE PRESENT FOR A PERIOD OF TIME WHENTHE SWITCH IS FIRST ENERGIZED. THE PERIOD OF TIME IS EQUALTO THE TIMER SETTING. TO AVOID STARTING THE ENGINE DUR-ING THIS TIME PERIOD, TURN THE GENERATOR CONTROLS TOTHE OFF POSITION.Energize the ATS equipment as described in Sections 6.1.2through 6.1.6. Insure that all safety precautions are taken andthat all WARNINGS and CAUTIONS are observed.6.1.2 No Voltage StepsWith no voltage available on either power source, proceed as fol-lows.Step 1: The generator engine start controls should be in the OFFposition to prevent an undesired start.Step 2: Ensure that the ATS has been set to the proper appliedsystem voltage (See Section 4.7).Step 3: Check all ATS loads to ensure that they are ready to beenergized.6.1.3 Connecting the Power SourcesStep 1: Close the Source 1 power source upstream protectiondevice.Step 2: Connect the engine start battery cable.Step 3: With the emergency generator in the OFF position, closethe Source 2 power source upstream protective device,assuming such a device used.