It's called tomorrow. You can't start next chapter of your life if you keep re-reading the last one. Success is the ability to go from one failure to another with no loss of enthusiasm. Only the people who dare to fail, will achieve big success. All glory comes from daring to begin.
The poorest of all people is not the person without a cent, but the person without a dream. Happiness is when what you think, what you say, and what you do are in harmony. Wear a smile and have friends; wear a scowl and have wrinkles. EMBED for wordpress. Want more? Advanced embedding details, examples, and help! Publication date Usage CC0 1. Org Contributor Public.
Org Language English. In order to promote public education and public safety, equal justice for all, a better informed citizenry, the rule of law, world trade and world peace, this legal document is hereby made available on a noncommercial basis, as it is the right of all humans to know and speak the laws that govern them. In accordance with IEC [9], which gives guidance for the specification of permissible temperatures, the permissible temperature limits for bare copper and bare copper alloy parts can be equalized to the values for silver-coated or nickel-coated parts in the case of SF 6 atmospheres.
In the particular case of tin-coated parts, due to fretting corrosion effects refer to IEC an increase of the permissible temperatures is not applicable, even under the oxygen-free conditions of SF 6. Therefore, the initial values for tin-coated parts are kept. Point 6: The quality of the coated contacts shall be such that a continuous layer of coating material remains in the contact area.
According to the relevant specifications for each equipment. Point 8: The values of temperature and temperature rise are valid even if the conductor connected to the terminals is bare. Point 9: At the upper part of the oil.
Point Special consideration should be given when low flash-point oil is used in regard to vaporization and oxidation.
Point The temperature shall not reach a value where the elasticity of the material is impaired. Refer also to IEC [10]. Point Limited only by the requirement not to cause any damage to surrounding parts. Point These values are for connections to bare uninsulated cables or bus conductors. The standard value of rated short-time withstand current for new design should be selected from the R10 series and shall be equal to the short-circuit rating assigned to switchgear. The historic values of 6 A and 12 A, are also considered as preferred values.
NOTE The R10 series comprises the numbers 1 — 1,25 — 1,6 — 2 — 2,5 — 3,15 — 4 — 5 — 6,3 — 8 and their products by 10 n. This capability is demonstrated by the standard operating duty test defined in 6. Optional preferred values are 1 s, 2 s and 3 s. The resulting ranges of acceptable operation are similar, but not identical. See Annex I for ratings for hydraulically controlled series-trip reclosers and oil interrupting reclosers.
NOTE 2 The R10 series comprises the numbers 1 — 1,25 — 1,6 — 2 — 2,5 — 3,15 — 4 — 5 — 6,3 — 8 and their products by 10 n. See 3. The values given in Table 6, Table 7, Table 8, Table 9, Table 10 and Table 11 are prospective transient recovery voltage values for the test circuits. In the applications where more severe TRV conditions exist, additional test requirements may be required.
See Annex F and Annex G for additional information on the definition and application of reclosers and fault interrupters. In systems where reclosers are applied with a rated voltage up to 38 kV, the transient recovery voltage approximates to a damped single frequency oscillation. This envelope is the straight-line boundary of a TRV with the 1-cosine wave shape produced by typical distribution circuits. The influence of local capacitance on the source side of the circuit breaker produces a slower rate of rise of the voltage during the first few microseconds of the TRV.
This is taken into account by introducing a time delay. These parameters may be used for purposes of specification of TRV. The transient recovery voltage corresponding to the rated symmetrical interrupting current when a terminal fault occurs, is used for testing at short-circuit breaking currents equal to the rated value.
The first-pole-to-clear factor is a function of the distribution system earthing grounding and the characteristics of the switchgear itself. The first-pole-to-clear factor of 1,5 is used making the voltage experienced by the first-pole-to-clear equal to 1,5 times line to neutral voltage. A first-phase- to-clear factor of 1, is used since the voltage experienced by the first-pole-to-clear is equal to 1, times line to neutral voltage, which is the full phase-to-phase voltage.
This accounts for the fact that with a large separation in the times at which the interrupters open, the worst case is that one interrupter sees the full phase-to-phase voltage. Examples of this condition are three independent single-phase reclosers operating in a cluster on a three-phase distribution feeder or a set of three single-phase reclosers operating from a common control typically referred to as a triple-single recloser.
Although reclosers may be applied on solidly earthed grounded systems, the basis of rating and test requirements are for unearthed ungrounded systems using a first-phase- to-clear factor of 1,5 or 1, as explained in a above.
NOTE 2 Three-phase testing with an effectively earthed grounded circuit may require special consideration by a test laboratory. Any consideration of such tests should be by agreement among the manufacturer, user and the test laboratory. TRV values for these applications are covered in Table 6 and Table 7. The added capacitance of the cables slows down the TRV. TRV values for these applications are covered in Table 8 and Table 9. TRV values for these applications are covered in Table 10 and Table For fault interrupters of all interrupting ratings, the TRV values in Table 10 and Table 11 shall apply based on a cable-connected circuit.
See 4. These applications are outside the scope of this standard and shall be discussed with the manufacturer. Additional information on this subject can be found in IEC Refer to 4. NOTE 1 The standard operating duty for lines 2, 3, and 4 represent the half-life as measured by contact erosion. Other sequences may be used where O represents an open operation; CO represents a closing operation followed by an opening operation with a time delay controlled by the automatic control of the device.
Other reclosing intervals may be used. The operating sequence and reclosing intervals represent the minimum required capability of the device and shall be demonstrated in the standard operating duty test specified in 6. Other operating sequences, delays and reclosing intervals may be available for selection by the user. Table 13 — Preferred line and cable charging interrupting current ratings Rated maximum Maximum current voltage A r.
The peak current of the first major loop shall be as defined in 4. NOTE 2 Customer user preferences or local codes for indicators should be specified by the user. The operating lever shall be suitable for operation with a hot line stick. These special applications should be specified by the user. The voltages of the main circuit before disconnection shall be taken as the lowest voltage of the system associated with the rated voltage of the switching device. For sealed-pressure systems, these devices are not required.
NOTE It should be stated whether pressures or densities are absolute or relative values. If the switchgear consists of several poles with independent operating mechanisms, each pole shall be provided with a nameplate. This requirement does not apply if all of the pole mechanisms are mounted to a common structure. The nameplate shall be securely attached to the top of the tank by means of stainless steel screws, rivets, or other corrosion resistant fasteners.
All letters, schematics and numbers shall be permanently stamped, embossed or engraved on the nameplate. NOTE 1 The abbreviation in column 2 may be used instead of the term in column 1. In the absence of user specifications, the preferred colors to indicate an open or closed position are red to signify closed and green to signify open. Subclause 5. Refer to IEC [17].
These standards may be used by agreement between the user and the manufacturer. Values for other materials are under consideration. The permissible values shall be given by the manufacturer. The value for the time between replenishment shall be at least 10 years for SF 6 systems and for other gases should be consistent with the tightness values.
The possible leakages between subassemblies having different pressures shall also be taken into account. In the particular case of maintenance in a compartment when adjacent compartments contain gas under pressure, the permissible gas leakage rate across partitions should also be stated by the manufacturer, and the time between replenishments shall be not less than one month.
Means shall be provided to enable gas systems to be safely replenished while the equipment is in service. The expected operating life with regard to leakage performance shall be specified by the manufacturer. Preferred values are 20 years, 30 years and 40 years. They shall be designed and located on the tank to avoid interference between lifting slings and any attachments bushings, operating handles, etc , and to avoid scratching or marring the tank finish during handling.
The counter shall be visible with the recloser in service. This feature is not required for fault interrupters. As an alternative, red letters on a white background for both indicators may be used. Refer to Annex E for tolerances applied to test values.
An example of grouping is shown in Table Reconditioning is not permitted during any individual type test. The complete standard operating duty test specified in 6.
Manufacturer shall include in the information provided to the testing laboratory sufficient information to identify the control used in the design tests. Where appropriate, this information shall include model number, serial number, firmware revision, software revision and other appropriate control software information.
The definition of a cutout mounted recloser includes a fuse type mounting or support. This mounting or support is integral to the dielectric capability of the device. Manufacturer shall include in the information provided to the testing laboratory sufficient information to identify the mounting or support used in the design tests.
Where appropriate, this information shall include make, model number and rating. The definition of an automatic circuit recloser includes its automatic control. The control shall be considered an essential part of the switchgear in the test report including its model number, serial number, firmware revision, software revision and other appropriate control schemes. This mounting or support shall be considered an essential part of the switchgear and noted in the test report including its make, model number and rating.
A cutout mounted recloser may require the temporary attachment of an auxiliary device to perform the related switching functions of a recloser.
The distance between the terminals and the nearest supports of the conductors on both sides of the switchgear shall be in accordance with the instructions of the manufacturer; e a cutout mounted recloser may require the temporary attachment of an auxiliary device to perform the related switching functions of a recloser. If such a device is required, it need not be mounted except for those tests requiring its use; f the test arrangement shall be noted in the test report.
If the control apparatus is intended by the manufacturer to always be integrally mounted to or within the recloser structure it shall be considered in compliance with a and b above with a zero length control cable.
Rated insulation levels for cutout mounted reclosers are based in part on the rating of the fuse support or base identified by the manufacturer in 6. Refer to Clause for field-testing. WARNING When performing tests involving open contacts in vacuum, adequate precautions such as shielding or distance should be used to protect test personnel against the possible occurrences of higher X-radiation due, for example, to incorrect contact spacing, or to the application of voltages in excess of those specified.
Further discussion of shielding, adequate distances and personnel exposure limits are found in ANSI C These bare wires shall project in such a manner as not to decrease the withstand value.
Any necessary bends may be made at the terminals. The test lead connections shall be made to the wires projecting from the terminals. If terminations capable of meeting the specified dielectric voltage are not available, other terminations bushing or connectors, or both may be substituted for the purpose of performing these tests. The connections of the terminals for phases B and C are not applicable.
If the operating sequence allows the device to rest with an open interrupter gap and a closed disconnector gap, both the isolation gap alone and the interrupter gap alone shall be tested for the open position test cases. The test duration shall be 60 s for the dry test. When used, the test voltage applied shall be the value given in column 7 of Table 3.
DC or very low frequency test voltages are used on cables that still may be connected to the switchgear. This design test is included to verify that the switchgear can also withstand the same test voltage.
Refer to Clause for a discussion on field tests. The test shall be considered to have failed if there is: a a leakage current of more than 10 mA, or b the test device is unable to withstand the voltage. The test shall be considered to have passed if the test device withstands the test voltage with a leakage current that does not exceed 10 mA. Non-sustained disruptive discharges NSDD may occur and are allowed. NOTE These test criteria recognize the likelihood that a small leakage current may pass through an insulating medium or across an insulating surface while still supporting the high d.
This is particularly true of vacuum interrupters. If the creepage distances do not comply with the requirements of IEC , artificial pollution tests should be performed according to IEC , using the rated voltage and the application factors given in IEC RIV tests are not a requirement of this standard. The recloser shall have a conductor connected to each terminal having a minimum length of 1,2 m.
For aluminum cables use Table The connection shall be made to the ends of these conductors. The ambient temperature shall be determined by taking the average of the readings of three measuring devices placed mm to one side of the device and vertically located as follows: Pole or frame mounted equipment Enclosed equipment mm above the top of the device Level with the top of the equipment mm below the bottom of the device mm 12 in above the floor Midway between the two previous positions Midway between the two previous positions NOTE Pole or frame-mounted equipment includes all equipment mounted above or off the floor or ground.
Enclosed equipment includes metal clad, metal enclosed and pad-mounted equipment that is normally installed on the floor or ground pad.
The thermometers or thermocouples shall be protected against air current and undue influence of heat. NOTE In order to avoid indication errors because of rapid temperature changes, the thermometers or thermocouples may be put into a suitable liquid such as oil in a suitable container or reliably attached to a suitable mass of metal.
During the last quarter of the test period, the change of ambient air temperature shall not exceed 1 K in 1 h. No correction of the temperature-rise values shall be made for ambient air temperatures within this range. The current in the other outer phase shall begin with a major loop. If two separate tests are made, the time during which the short-circuit current is applied in the peak withstand current test shall be not less than 0,3 s.
Leakage rates at extreme temperatures shall not exceed the values in Table In general, the test Q m see IEC [21] represents an adequate method to determine leakage in gas systems.
There is no requirement to test new switchgear designs using vacuum interrupters that have been previously tested for X-radiation. The tests are also applicable to the case of an overhead line in series with short lengths of cable. NOTE 1 Single-phase reclosers are frequently applied in a set of three on a three-phase circuit.
Accordingly, single-phase reclosers are required to meet the line and cable charging current tests. The purpose of these tests is to demonstrate the ability to interrupt the capacitive component of currents associated with the line and cable charging interrupting current ratings of the recloser.
In any case, the total current shall not exceed the rated line charging interrupting current. Phenomena occurring after a restrike or a reignition event are not representative of service conditions as the test circuit does not adequately reproduce the post-event voltage conditions. Tests at 60 Hz may be considered to prove the breaking characteristics at 50 Hz. This implies that the peak of a 50 Hz source voltage will be greater than a test at 60 Hz.
If a restrike occurs after 8,3 ms, due to the instantaneous voltage being higher than it would be during a test at 60 Hz, then the test-duty should be repeated at 60 Hz. The prospective transient recovery voltage of the supply circuit shall be no more severe than the transient recovery voltage specified for short-circuit test duty T Inrush currents may be controlled using a damping circuit. The preferred rating for line and cable charging current switching is for the more severe case of the unearthed system.
Higher values may unduly influence the recovery voltage. For three-phase tests representing three-core belted cables, the positive sequence capacitance shall be approximately twice the zero sequence capacitance. This condition is considered to be satisfied if the ratio of the r. The current to be interrupted shall not go through zero more than once per half-cycle of power frequency. Three-phase tests may be performed for either unearthed systems or solidly earthed systems as described in 6.
The power frequency test voltage and the d. Most test laboratories can handle the switching test requirements of this standard without having to resort to single-phase testing for verification of three-phase performance. As an alternative, the preconditioning test may consist of the following: 1 same current as test-duty T20; 2 no specified TRV; 3 at least four opening operations. NOTE 1 The manufacturer may choose to perform additional iterations of the T20 preconditioning tests.
NOTE 2 Arcing times will be set random. The capacitive current switching tests shall consist of the test-duties as specified in Table A reignition followed by interruption at a later current zero shall be treated as a breaking operation with a longer arcing time.
For each test the arcing time should be set randomly. Restrikes that occur within the first 0,3 s from initial clearing shall count towards the three restrike maximum; tests that withstand for 0,3 s, but restrike after 0,3 s shall be considered invalid and shall be repeated. NOTE The voltage magnitude after clearing can escalate with multiple restrikes and test labs may shut power off to protect their equipment.
If 0,3 s of withstand have not occurred then a successful operation was not made based on 6. Demonstration of the making current capability for non-interrupting gaps shall be in a fault closing test using the method of closing intended for that gap. Three closing operations without maintenance shall be performed on the same specimen.
Conversely, if the three poles operate from independent mechanisms and the interrupting medium does not allow contamination from arcing between the phases during interruption, then single phase testing is permitted.
This simulates application on multi-earthed wye Y systems. If single-phase tests are made, a earth shall be placed on the test circuit.
The TRV impedances may be configured into a single series- parallel network. The current shall be calculated in accordance with Annex J. In this case the source side shall be connected to the source voltage. Test reports shall record the actual inherent TRV values of the test circuit along with the voltage and current values of each individual test operation.
See note below. If the testing laboratory is unable to meet the specified values of t 3 at the T20 and T50 current levels given in Table 6, Table 7, Table 8 and Table 9, it shall be permissible to use a higher value for t 3 , as long as it is less than the value specified for the T current level and provided that the TRV voltage peak meets the peak voltage requirement u c.
The actual inherent TRV values used for the test shall be stated in the test report. Thus, the test transient recovery voltage during an actual test may differ from the inherent TRV obtained in a TRV calibration test.
Refer to Annex A. If two such interruptions are not obtained in the operating duty tests, additional tests as specified in 6. If a different recloser is used to fulfil this requirement, the two interruptions shall be made on the second recloser.
0コメント