S&C Circuit-Switchers — Mark VI Inspection Recommendations To ensure Mark VI Circuit-Switcher’s continued proper performance, it should be inspected in accordance with the recommended schedule and procedures contained in the tables of this publication. Table I indicates the fre quency with which each major Circuit-Switcher compo nent should be inspected and Table II lists a summary of inspection procedures appropriate for each component. The actual number of open-close operations which may be obtained for a component in service will depend upon the nature of the application, the installation environment (e.g., whether subject to temperature or humid ity extremes, or highly corrosive or dusty atmospheres), and the observance of the recommended inspection schedule. An inspection frequency is shown for each component listed. To maximize the operating life of the component, it is recommended that the user perform the inspection pro cedures described in Table II, at the frequency indicated by a “d”—either in number of open-close operations or years, whichever occurs more often. If the inspection results so indicate—or if dictated by the mechanical-operations test value or electrical-operations limit guideline—the component should be replaced. Each user’s own experience will determine whether more frequent inspections are required. Outdoor Transmission (69 kV through 138 kV) Table I—Recommended Inspection Schedule A mechanical-operations test value is indicated in Table I for the Circuit-Switcher components affected by the number of mechanical operations performed. It is offered as a guideline to the number of open-close operations which might reasonably be expected before replacement is required. Electrical-operations limits are also listed for the inter rupter and disconnect live parts, since these components are affected by the number of electrical operations per formed. These limits are dependent upon the CircuitSwitcher application and magnitude of current switched. For the interrupter and disconnect live parts, the electri cal-operations limit may thus provide an overriding guide line to the number of open-close operations which might be expected before replacement is required. July 16, 2012© S&C Electric Company Table II—Recommended Inspection Procedures The Circuit-Switcher inspection procedures to be followed are summarized in Table II. The applicable S&C instruction sheets for the Circuit-Switcher, pre-insertion inductor, grounding switch, etc., should be referenced for further details. Data Bulletin 712-90 S&C Circuit-Switchers — Mark VI TABLE I—RECOMMENDED INSPECTION SCHEDULE FOR S&C CIRCUIT-SWITCHER COMPONENTS Component MechanicalOperations Test Value1, Number of Open-Close Operations Switch Operator and Power Train Interrupter 5 000 Disconnect Live Parts 5 000 — — — d d Transformer or Capacitor Switching 420 5 000 d dj 31 000 3 18 900 5 9 450 10 3 150 30 — — — d d Transformer or Capacitor Switching 420 5 000 d d Fault Closing 30 000 2 Pre-Insertion Inductor — — — — Grounding Switch — — — — 1 Based on mechanical-operations tests performed by S&C utilizing new Circuit-Switchers, with no intervening maintenance performed. 2 Frequently operated Circuit-Switchers (typically 200 or more openclose operations per year) should be inspected after the first 250 operations; thereafter, they should be inspected at the frequency indicated. Fre quently operated Circuit-Switchers also require annual lubrication of the disconnect live parts. See Table II. 2 S&C Data Bulletin 712-90 Number of Years Number of Open-Close Operations 5 000 5 000 Number of Open-Close Operations Maximum Current, Amperes Application Fault Interrupting Interrupter Charging Motor Inspection Frequency2 Electrical-Operations Limit d 1 or 2 250 2 500 1 5 Not applicable Not applicable d d d d Recommended inspection frequency. Frequently operated Circuit-Switchers equipped with pre-insertion inductors require annual cleaning of the inductor windings. See Table II. j The gas-pressure gauge on the underside of each interrupter should be checked for low gas density during the user’s normal day-to-day oper ating routine. S&C Circuit-Switchers — Mark VI TABLE II—RECOMMENDED INSPECTION PROCEDURES FOR S&C CIRCUIT-SWITCHER COMPONENTS Component General Switch Operator Inspection Procedures 1. Check with your local S&C Sales Office for any outstanding Field Notifications for inspection, retrofit, or maintenance on your model switch. 2. Check the switch for overall cleanliness of the insulators, live parts, and operator. Power washing with water or a non-abrasive cleaning method should be performed for severe contamination. Reapply lubricant to the live parts after washing. 1. 2. 3. 4. Check for evidence of water ingress, damage, excessive corrosion, or wear. Check ease of operation during slow, manual cranking using the switch operator manual operating handle. Check electrical operation, coupled and decoupled. Check for loose wiring inside enclosure and proper functioning of position-indicating lamps, operation counter, conve nience lamp, etc. 5. Check operation of brake and readjust if necessary. Power Train 1. Check for evidence of damage, excessive corrosion, or wear. 2. Check tightness of fasteners. 3. Observe operation during slow, manual cranking using the switch operator manual operating handle. Check for complete stroking of the various drive levers against their stops and for attainment of overtoggle positions, as required. 4. Check condition of seals. Interrupter1 1. 2. 3. 4. 5. Interrupter Charging Motor 1. Check for evidence of water ingress, damage, excessive corrosion, or wear. 2. Check tightness of fasteners—especially at the connection between the motor and the interrupter operating shaft. 3. Check alignment of the connection between the interrupter and the charging motor. The hook that secures the motor to the interrupter should move freely. Disconnect Live Parts 1. Check for evidence of damage, excessive corrosion, or wear—especially at the fault-closing contacts and current-carrying contacts. Replace current-carrying jaw contacts if the silver-alloy inserts on two or more contact fingers are worn to the extent that the blade tongue contact engages the full width of the contact finger. 2. Check tightness of fasteners on current-carrying parts. 3. Observe operation during slow, manual cranking using the switch operator manual operating handle. Check for proper contact alignment. 4. Lubricate the contact surfaces with an appropriate lubricant. Shell Gadus® S2 U1000 2 Lubricant Catalog Number 9999‑043 is available in 1 oz. tubes from S&C. Shell Darina SD2, Dow 33, or equivalent can be substituted. 5. Check for excessive corrosion at the terminal pad and interrupter-to-disconnect bus. 6. Check for evidence of excessive terminal-pad loading. Pre-Insertion Inductor 1. Clean the exterior finish of inductor windings using mild soap and water solution and a soft cloth. Inspect the fiberglass roving for damage or wear. Use a mild soap and water solution and a clean cloth to clean the exterior finish of the inductor winding. While cleaning the windings, inspect for damage or exposure of the fiberglass roving. 2. If the fiberglass roving is damaged, use the touch-up kit, S&C Catalog Number SA‑42721, to refinish any damaged surfaces. First, thoroughly wire-brush the surface to be refinished. Then, sand with No. 1 sandpaper and No. 0 sandpaper to create a smooth surface. Brush on the paint according to the directions on the label, and dry for six hours. If the coiled conductor beneath the fiberglass roving is exposed, remove the inductor from service and contact your nearest S&C Sales Office for a replacement. 3. Inspect the moving and stationary arcing rods to verify their proper setting. Replace the arcing rods if they show significant wear or erosion. Grounding Switch 1. 2. 3. 4. Check gas-pressure gauge (on underside) for low gas density. Check tightness of fasteners on current-carrying parts. Check for discoloration, contamination, or other damage to the interrupter insulation. Check for excessive corrosion at the terminal pad and interrupter-to-disconnect bus. Check for evidence of excessive terminal-pad loading. Check for evidence of damage, excessive corrosion, or wear—especially at the jaw contacts. Check tightness of fasteners on current-carrying parts. Observe operation using manual operating handle. Check for proper contact alignment. Lubricate the contact surfaces with an appropriate lubricant. Shell Gadus® S2 U1000 2 Lubricant Catalog Number 9999‑043 is available in 1 oz. tubes from S&C. Shell Darina SD2, Dow 33, or equivalent can be substituted. 1 Mark VI Circuit-Switcher interrupters should have resistance values under 200 micro-ohms when new, and under 500 micro-ohms when in service. If an interrupter has a resistance value outside this range, contact your nearest S&C Sales Office. S&C Data Bulletin 712-90 3 Printed in U.S.A.