IEC 60252 2 pdf download – AC motor capacitors – Part 2: Motor start capacitors

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IEC 60252 2 pdf download – AC motor capacitors – Part 2: Motor start capacitors

IEC 60252 2 pdf download – AC motor capacitors – Part 2: Motor start capacitors
1General
1.1scope and object
This International Standard applies to motor start capacitors intended for connection towindings of asynchronous motors supplied from a single-phase system having the frequencyof the mains.
This standard covers impregnated or unimpregnated metallized motor start capacitors havinga dielectric of paper or plastic film,or a combination of both and electrolytic motor startcapacitors with non-solid electrolyte, with rated voltages up to and including 660 v.
1.2Normative references
The following referenced documents are indispensable for the application of this document.For dated references, only the edition cited applies.For undated references, the latest editionof the referenced document (including any amendments) applies.
IEC 60068-2-6:1995,Environmental testing -Part 2: Tests – Test Fc: Vibration (sinusoidal)IEC 60068-2-14:1984,Environmental testing – Part 2:Tests -Test N: Change of temperatureIEC 60068-2-20:1979,Environmental testing – Part 2: Tests – Test T: Soldering
IEC 60068-2-21:1999,Environmental testing – Part 2-21: Tests – Test U: Robustness ofterminations and integral mounting devices
IEC 60068-2-78:2001,Environmental testing – Part 2-78: Tests – Test Cab: Damp heat,steady state
IEC60112:1979,Method for determining the comparative and the proof tracking indices ofsolid insulating materials under moist conditions
IEC 60309-1:1999,Plugs,socket-outlets and couplers for industrial purposes – Part 1:General requirements
IEC60529:1989,Degrees of protection provided by enclosures (IP Code)
IEC 60695-2-10:2000,Fire hazard testing – Part 2-10: Glowing/hot-wire based test methods- Glow-wire apparatus and common test procedure
IEC 60695-2-11:2000,Fire hazard testing – Part 2-11: Glowing/hot-wire based test methods -Glow-wire flammability test method for end-products
IsO 4046: Paper,board, pulps and related terms – Vocabulary
1.3Definitions
For the purposes of this document,the following definitions apply.
1.3.1
motor running capacitor
power capacitor which,when used in conjunction with an auxiliary winding of a motor,assiststhe motor to start and improves the torque under running conditions
NOTE The running capacitor is usually connected permanently to the motor winding and remains in circuitthroughout the running period of the motor. During the starting period,if it is in parallel with the starting capacitor,it helps to start the motor.
1.3.2
motor starting capacitor
power capacitor which provides a leading current to an auxiliary winding of a motor and whichis switched out of circuit once the motor is running
1.3.3
metal foil capacitor
capacitor, the electrodes of which consist of metal foils or strips separated by a dielectric
1.3.4
metallized capacitor
capacitor, in which the electrodes consist of a metallic deposit on the dielectric
1.3.5
self-healing capacitor
capacitor, the electrical properties of which,after local breakdown of the dielectric,are rapidlyand essentially self-restored
1.3.6
discharge device of a capacitor
device which may be incorporated in a capacitor, capable of reducing the voltage between theterminals effectively to zero, within a given time, after the capacitor has been disconnectedfrom a network
1.3.7
continuous operation
operation with no time limit within the normal life of the capacitor
1.3.8
intermittent operation
operation in which periods with the capacitor energized are followed by intervals during whichthe capacitor is unenergized
1.3.9
starting operation
special type of intermittent operation in which the capacitor is energized for only a very shortperiod while the motor is accelerating to rated speed
1.3.10
rated duty cycle
rated value indicating the rate of intermittent or starting duty for which a capacitor is suitable.lt is specified by the duty cycle duration,in minutes, and the percentage of the time duringwhich the capacitor is energized
1.3.11
duty cycle duration
total time of one energized and one unenergized interval during the intermittent operation
1.3.12
relative operation time
percentage of the cycle duration in which the capacitor is energized
1.3.13
capacitor for continuous and starting operation
capacitor designed to operate at one voltage when in continuous operation and at a different(usually higher) voltage when in starting operation
1.3.14
minimum permissible capacitor operating temperature
minimum permissible temperature on the outside of the case at the moment of switching onthe capacitor
1.3.15
maximum permissible capacitor operating temperature (te)
maximum permissible temperature of the hottest area of the outside of the capacitor caseduring operation
1.3.16
rated voltage of a capacitor (uN)
r.m.s. value of the alternating voltage for which the capacitor has been designed1.3.17
maximum voltage
maximum r.m.s. voltage permissible at the starting capacitor terminals between the point ofstarting and the instant at which the capacitor is disconnected
1.3.18
rated frequency of a capacitor ()
highest frequency for which the capacitor has been designed