0302_A_HV-SS-EMERGENCY_SWITCHBOARD_CLEANING_Rev_1.doc

USNS MEDGAR EVERS

(T-AKE 13)

28 April 2014

HV-SS-E SWITCHBOARD Cleaning and Maintenance Rev 1

1.0 ABSTRACT:

1.1 Provide qualified service technicians to perform cleaning and Maintenance on the Main, Ships Service, and Emergency Switchboards including breaker maintenance.

2.0 REFERENCES/ENCLOSURES:

2.1 References:

2.1.1 NAVSEA T/M T9235-AL-MCC-010, Main Power Switchboard, 6.6 KV, 2500A

2.1.2 NAVSEA T/M T9324-BU-MMC-010, Switchboards Ships Service 480V

2.1.3 NAVSEA T/M T9324-BT-MMC-010, Emergency Switchboard 480V Dwg 2838 For TAKE

2.1.4 Cutler Hammer, I.B. 32-255-1G, Instructions for Installation, Operation and Maintenance of Type VCP-W Vacuum Circuit Breakers

2.1.5 Cutler Hammer, I.B. 48002, Instructions for 36" Wide Vacuum-Break Starters Rated 360 Amperes, 7200 Volts, Roll Out Type

2.2 Enclosures: None

3.0 ITEM LOCATION AND DESCRIPTION:

3.1 Location:

3.1.1 Main Switchboard: 3-72-0, High Voltage Switchboard Rm

3.1.2 SS Switchboard: 3-66-02, EOS

3.1.3 Emergency Switchboard: 02-73-1, EDG Rm

3.2 Description:

3.2.1 Main Switchboard #1 and #2: 6.6KV, 2500A, 3Ø, 3W 60Hz, 41 KA RMS System, Point Eight Power, Dwg 2876. Consisting of 2 each buses, including 16 sections total.

3.2.2 SS Switchboard #1 and #2: 480V, 6500A, 3Ø, 3W 60Hz, 100 KA RMS System, Point Eight Power, Dwg 2835. Consisting of 2 each buses, with 9 sections per bus and a bus transition section.

3.2.3 Emergency Switchboard: 480V, 4000A, 3Ø, 3W 60Hz, 85 KA RMS System, Point Eight Power, Dwg 2838. Consisting of 1 each bus with 11 sections

3.2.4 Main Switchboard Breakers:

3.2.4.1 Three (3) each, 2000 Amp Cutler Hammer 75VCP-W-500

3.2.4.2 Ten (10) each, 1200 Amp Cutler Hammer 75VCP-500

3.2.5 Main Switchboard Contactors:

3.2.5.1 Fifteen (15) each, Cutler Hammer Model SJA 7.2 KVA 400 A Vacuum Roll out Full Voltage-Non Reversing Latching Contactor Assembly with test plug and receptacle.

3.2.6 Ship's Service Switchboard Breakers:

3.2.6.1 Four (4) each, Cutler Hammer Model Magnum IEC breaker 6300 AF , 100 KA , 3 Pole ABCABC Draw out, 6300 Amp Sensor/plug 520 LSI Trip unit with 110/120 VAC/VDC Shunt Trip 110/125 5 sec motor operator 110/127VAC/VDC spring release, 110/120 VAC undervoltage Release, 6a/6b Auxiliary Contacts

3.2.6.2 Four (4) each, Cutler Hammer Model Magnum DS breaker 4000AF, 100KA, 3 Pole ABCABC, Draw out, 400 A sensor/Plug 520 LIS trip with 110/127 VAC/VDC Shunt trip, 110/125VAC 5 sec motor operator, 110/127 VAC/VDC spring release.

3.2.7 Emergency Switchboard Breakers:

3.2.7.1 Three (3) each, Whipp and Bourne, ACB 4000hr, 4000AF, 3 pole, 500VAC 85000AIC, 80KA Max fixed inst, trip, 480VAC control Power 115/120VAC Close and shunt trip Voltage, 480VAC UVR, 4a/5b Aux Contacts

4.0 GOVERNMENT FURNISHED EQUIPMENT/MATERIALS/SERVICES:

4.1 None.

5.0 NOTES:

5.1 This ship contains High Voltage (HV) electrical systems. The contractor and subcontractors shall obey all posted and verbal instructions regarding safety and exclusion from High Voltage areas. At no time shall a contractor or subcontractor approach, work on, or enter a High Voltage area with out proper authorization.

5.2 THE USNS MEDGAR EVERS ELECTRICAL COLOR CODING DOES NOT FOLLOW CONSISTENT COLOR SCHEME. THE SHIP IS KNOWN TO HAVE CURRENT CARRYING CONDUCTORS COLORED GREEN, BLUE, BLACK AND WHITE. THE CONTRACTOR SHALL ASSUME ALL ELECTRICAL CABLES ARE HOT UNTIL TESTED OTHERWISE. THE CONTRACTOR SHALL TEST ALL ELECTRICAL CABLES TO ENSURE THEY ARE DEAD PRIOR TO WORK ON THE ITEM.

5.3 Before starting work, all equipments shall be locked out and tagged out using the ship’s HV lock out procedures, and the ship's LV lock out procedures. Switchboards shall be proven dead prior to beginning any work.

5.4 Under torquing or over torquing may produce overheating and / or cause damage to the conductor.

5.5 Do not apply insulation test voltage to electronic devices or equipment with solid state components.

5.6 Compressed air should be avoided because it may force dirt and dust into coil insulation.

5.7 Do not work on breaker/contactor element with primary power applied.

5.8 Do not work on a breaker/contactor element with secondary contacts connected.

5.9 Do not defeat any safety interlocks.

5.10 Do not leave maintenance tool in the socket after charging the closing springs.

5.11 Always remove the breakers/contactor form the enclosure before performing any maintenance. Failure to do so could result in electrical shock leading to death, server personal injury or property damage.

6.0 QUALITY ASSURANCE REQUIREMENTS: None additional

7.0 STATEMENT OF WORK:

7.1 Shipyard shall provide contractors listed under "manufacturer’s representatives" to perform all work under this item. Shipyard shall assist and provide scheduling of other work during the yard period to support this item.

7.2 Breaker and Contactor Repair:

7.2.1.1 Tech rep shall troubleshoot and repair the following breakers and contactors that currently fail to open upon loss of power.

-All HV SWBD #1 Load Center contactors,(LC1, LC3, LC5, LC7, LC9 and LC11) -Main SWBD Bus Tie Bkr, (CB5)

-Main SWBD #1 SS SWBD transformer (CB7)

-SS SWBD Bus Tie Bkr, (CB11)

-SS SWBD #2 to E-SWBD BKR (CB15)

7.3 High Voltage Switchboard:

7.3.1 Cleaning:

7.3.1.1 Open switchboard sections for cleaning access.

7.3.1.2 Clean and torque the switchboard in accordance with reference 2.1.1

7.3.1.3 MSCREP/Ships Force shall perform final close out inspection.

7.3.2 Switchboard Inspection:

7.3.2.1 Inspect HV switchboard for any damage and proper functioning.

7.3.3 HV Breaker Maintenance:

7.3.3.1 All HV breaker maintenance shall be performed by an Authorized OEM Rep.

7.3.3.2 Refer to reference 2.1.1 and 2.1.4 for detailed procedures.

7.3.3.3 Rack out and remove for inspection and maintenance all the switchboard breakers and contactors.

7.3.3.4 Visually inspect drive insulator, barriers and stand-off insulators for dirt and cracking. Clean with lint free cloth or replace cracked piece.

7.3.3.5 Check the insulation integrity of the Main Circuit to Ground, between Main circuit Terminals and Control circuit to ground with a hip potential (Hipot) tester as follows:

Note: The test voltage depends upon the maximum rated voltage of the breaker. For breaker elements rated at 8.25 KV, the test voltage is 27 KV.

7.3.3.5.1 Remove circuit breaker from the switchboard in accordance with Reference 2.1.1. to perform the following tests.

7.3.3.5.2 Close the breaker. Connect the High Potential lead of the test machine to one of the poles of the breaker. Connect the remaining poles and breaker frame to ground.

7.3.3.5.3 Start the machine with output potential at zero and increase to the test voltage. Maintain the test voltage for one minute. Repeat for the remaining poles. Successful withstand indicates satisfactory insulation strength of the primary circuit.

7.3.3.6 Visually check the vacuum interrupters by closing the circuit breakers and observing if all the green marks on the moving stems are visible. If a mark is not visible, perform a contact wipe check.

7.3.3.6.1 The adequacy of the contact wipe can be determined by observing the vacuum interrupter side of the operating rod assembly on a closed circuit breaker. Refer to tech manual for the procedure in determining the contact wipe of blue or red contact springs. If the wipe is not adequate, the vacuum interrupter assembly (pole unit) must be replaced. A field adjustment is not possible.

Note: Failure to replace a pole unit assembly when contact erosion mark is not visible or wipe is unsatisfactory will cause the breaker to fail to interrupt and thereby cause property damage or personal injury.

7.3.3.7 Vacuum Interrupters used in Type VCP-W Vacuum Circuit Breaker Elements Are highly reliable interrupting elements. Satisfactory performance of these devices is dependent upon the integrity of the vacuum in the interrupter and the internal dielectric strength. Both these parameters can be easily checked by a one minute AC High Potential test.

Warning: Applying abnormally high voltage across a pair of contacts in vacuum may produce x-radiation. The radiation increases with the increase in voltage and or decreases in contact spacing. X radiation produced during this test with recommended voltage and normal contact spacing is extremely low and well below maximum permitted by standards. However, as a precautionary measure against possibility of application of higher than recommended voltage and or below normal contact spacing, it is recommended that all operating personnel stand at lest four meters away in front of the breaker element.

Warning: After the high potential is removed, an electrical charge may be retained by the vacuum interrupters. Failure to discharge the residual electrostatic charge could result in an electrical shock. All six primary terminals and the center ring of each vacuum interrupter of the circuit breaker should be grounded to reduce this electrical charge before coming in contact with the primary circuit.

7.3.3.8 Perform vacuum interrupter integrity test as follows:

7.3.3.8.1 With the breaker element open, connect all top primary studs (bars) together and to the high potential machine lead. Connect all bottom studs together and ground them along with the breaker frame. Start the machine at zero potential, increase to appropriate test voltage and maintain for one minute.

7.3.3.8.2 Test voltage is 27 KV AC 60hz, per reference 2.1.4 section 6-4.

7.3.3.8.3 A successful withstand indicates that all interrupters have a satisfactory vacuum level. If there is a breakdown, the defective interrupter or interrupters should be identified by an individual test and replaced before placing the breaker in service.

Note: To avoid any ambiguity in the AC hi potential test due to leakage or displacement (capacitive) current, the test unit should have sufficient volt ampere capacity. It is recommended that the equipment be capable of delivering 25 milliamperes for one minute.

7.3.3.9 Inspect the primary disconnects for evidence of burning or damage. Replace if burned, damaged or eroded,

7.3.3.10 Test the closing and tripping device including disconnects of the circuit breaker twice. Replace any defective device. Identify per troubleshooting chart in reference 2.1.4.

7.3.3.11 Visually check that wiring is securely tied in proper place. Repair or tie as necessary.

7.3.3.12 Visually check that the terminals are tight. Tighten or replace if necessary.

7.3.3.13 Conduct a functional test of the charging motor. Replace brushes if necessary or motor.

7.3.3.14 Make a careful visual inspection of the operating mechanism for any loose or missing parts. Tighten or reinstate if necessary with appropriate tools. Visually check for dust or foreign matter. Clean as necessary.

7.3.3.15 Check for the smooth operation of the operating mechanism. Check for deformation or excessive wear. Remove cause and replace parts if necessary.

7.3.3.16 Lubricate operating mechanisms very sparingly with light mineral oil; refer to reference 2.1.4 Figure 6-1 for lubrications points. After lubrication, operate the circuit breaker several times manually and electrically.

7.3.3.17 Check for smooth operation during manual charging, closing and tripping.

7.3.3.18 Conduct a Closure™ Test in accordance with reference 2.1.4 Section 6-9.1

7.3.3.19 Reinstall Breakers into switchboard.

7.3.4 HV Contactor Maintenance:

7.3.4.1 All HV Contactor maintenance shall be performed by and authorized OEM Rep.

7.3.4.2 Remove contactor from the switchboard.

7.3.4.3 Visually Inspect contactor for dirt and or grease and clean as needed with lint free cloth.

7.3.4.4 To verify the integrity of the vacuum interrupters a voltage of 16KV-AC should be applied across the open contacts of the interrupters. The voltage should be applied for 60 seconds without breakdown. Breakdown is defined as a current of 5mA or more flowing across the open contacts. Note that approximately 1.3mA of current will flow through each interrupter during the AC test due to the capacitance of the vacuum interrupter. If a DC high potential test unit is used, make certain that the peak voltage does not exceed 23KV, the peak of the corresponding AC RMS test voltage. A megger cannot be used to verify vacuum integrity due to its limited output voltage.

Warning: When a vacuum bottle is tested with voltage over 5000 volts across its open gap there is some possibility of generating X-rays. Test should be minimized and personnel should be not closer than 10 feet this is a precaution until such time as the possible hazard is better understood and standards are published.

Note: Periodic dielectric tests across open contacts should not be omitted on the basis of satisfactory contactor performance since under certain operating conditions, the contactor may perform satisfactorily even though one vacuum interrupter has become defective.

7.3.4.5 Contact material vaporizes from the contact faces during every interruption and condenses elsewhere inside the bottle. This is normal, and is provided for by overtravel or wear allowance. When the contactor is fully closed, there is a gap between the lower bottle nut and a pivot plate. As the contacts wear, this gap decreases. When the gap goes below 0.020 inches on any pole, all the bottle subassemblies should be replaced. Use the 0.020 inch thick fork shaped overtravel feeler gauge supplied for this measurement, part no 5259C11. DO NOT RE-ADJUST THE BOTTLE NUTS TO RESET OVER TRAVEL AS THE CONTACTS WEAR. Once the contactor is place in service, overtravel should be checked but not adjusted.

7.3.4.6 Inspect the primary disconnects for evidence of burning or damage. Replace if burned, damaged or eroded.

7.3.4.7 Test the closing and tripping device including disconnects of the contactor twice. Replace any defective devices.

7.3.4.8 Visually check that wiring is securely tied in proper place. Repair or tie as necessary.

7.3.4.9 Visually check that the terminals are tight. Tighten or replace if necessary.

7.3.4.10 Make a careful visual inspection of the operating mechanism for any loose or missing parts. Tighten or reinstate if necessary with appropriate tools. Visually check for dust or foreign matter.

7.3.4.11 Check for the smooth operation of the operating mechanism. Check for deformation or excessive wear. Remove cause and replace parts if necessary.

7.3.4.12 Reinstall all contactors into the switchboard.

7.4 Ship's Service Switchboard and Emergency Switchboard:

7.4.1 Cleaning:

7.4.1.1 Open all switchboard sections for cleaning access.

7.4.1.2 Clean and torque the switchboard in accordance with reference 2.1.2, and 2.1.3.

7.4.1.3 MSCREP/Ships Force shall perform final close out inspection.

7.4.2 Inspection:

7.4.2.1 Inspect SS and E switchboards for any damage and proper functioning.

7.4.3 Breaker Maintenance:

7.4.3.1 Remove breakers from enclosures.

7.4.3.2 Visually inspect breaker and enclosure for dirt and/ or grease and clean as needed with lint free cloth.

7.4.3.3 Inspect the primary disconnect fingers for evidence of burning or damage.

7.4.3.4 Test the closing and tripping device of the breaker twice. Replace any defective devices.

7.4.3.5 Visually check that wiring is securely tied in proper place. Repair or tie as necessary.

7.4.3.6 Visually check that the terminals are tight. Tighten or replace if necessary.

7.4.3.7 Conduct a functional test of the charging motor. Replace brushes if necessary.

7.4.3.8 Make a careful visual inspection of the operating mechanism for any loose or missing parts. Tighten or reinstate if necessary with appropriate tools. Visually check for dust or foreign matter.

7.4.3.9 Check for the smooth operation of the operating mechanism. Check for deformation or excessive wear. Remove cause and replace parts if necessary. Check for smooth operation during manual charging, closing and tripping.

7.4.3.10 Re install circuit breaker into enclosure.

7.5 Preparation of Report:

7.5.1 Prepare and submit service report outlining all actions taken including any corrective actions. The report shall include listing of all meters and gauges calibrated on the HV switchboard and the dates of their calibration.

7.6 Manufacturer's Representative:

-Manufactures representative shall be qualified to work on High Voltage equipment per MSC SMS Procedures

-Manufactures representative shall have been trained on equipment in HV, SS and emergency Switchboards.

Suggested Sources:

1. Cadick Corporation

Garland Texas, 75049-5578

Phone 972-240-1594

2. Point Eight Power

Engineers Road

Bella Chasse, LA www.pointeightpower.com Phone: 800 284-1522

504-394-6100

3. Miller Integrated Power and Controls

Phone: 757-312-0574 Ext 118

Cell: 757-536-4807

POC Mr Todd C. Babcock

8.0 GENERAL REQUIREMENTS: None additional

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