1、UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULNovember 15, 20061SUBJECT 508EOUTLINE OF INVESTIGATIONFORIEC TYPE 2 COORDINATION SHORT CIRCUIT TESTS OFELECTROMECHANICAL MOTOR CONTROLLERS IN ACCORDANCE WITHIEC PUBLICATION 947-4-1Issue Number: 3
2、NOVEMBER 15, 2006Summary of TopicsThis new issue of SU 508E is being issued through ULs electronicpublishing system to ensure format uniformity between the PDF andHTML versions of the document. No substantive changes have beenincorporated in the document.The UL Foreword is no longer located within t
3、he UL Standard. For informationconcerning the use and application of the requirements contained in thisStandard, the current version of the UL Foreword is located onULStandardsInfoNet at: http:/ 2006 UNDERWRITERS LABORATORIES INC.UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDIST
4、RIBUTION WITHOUT PERMISSION FROM ULNOVEMBER 15, 2006SUBJECT 508E2No Text on This PageUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULCONTENTSINTRODUCTION1 Scope .42 Normative References .43 Definitions 44 General 6CONSTRUCTION5 General 6PERFOR
5、MANCE6 Enclosure Tests 77 Conductors, Conduit, and Terminal Torque .78 Selection of Heater Elements .79 Calibration of Test Circuits .710 Power Factor Requirements .811 Ground Fuse (Link) Requirements .812 Recovery Voltage 913 Short Circuit Test at r .914 Short Circuit Test at Iq .1015 Type 2 Coordi
6、nation Criteria for Evaluation of the Test Results r and Iq 1015.1 General .1015.2 All devices .1015.3 Discrete-type combination motor controllers and starters provided with short circuitprotective devices 1115.4 Type 2 coordination for all devices 1116 Dielectric Voltage-Withstand Tests 1217 Overlo
7、ad Relay Calibration Tests .1318 Discrimination Between Overload Relay and Short Circuit Protective Device (Optional) 1318.1 General .1318.2 Condition for the test .1318.3 Test currents and test circuits 1318.4 Test procedure .1418.5 Results to be obtained 14NOVEMBER 15, 2006 SUBJECT 508E 3UL COPYRI
8、GHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULINTRODUCTION1 Scope1.1 The requirements in this Outline of Investigation are for verification of short-circuit tests to beconducted on Type 2 coordinated electromechanical motor controllers as defined by
9、and in accordancewith the Standard for Low Voltage Switchgear and Controlgear, Part 4: Contactors and Motor-Starters,International Electrotechnical Commission (IEC) Publication 947-4-1.1.2 These requirements cover electromechanical motor controllers, such as manually or magneticallyoperated contacto
10、rs with or without thermal or solid state overload relays, combination motor controllerswith discrete components, and starters that are provided with short circuit protective devices, that havebeen investigated for compliance with the requirements in the Standard for Industrial Control Equipment,UL
11、508, and where the main contact voltage rating does not exceed 1000 V ac or 1500 V dc.1.3 The requirements in this Outline of Investigation are applicable only to those specific motor controllersand short circuit protective devices (SCPD) which have been coordinated together by the manufacturer.2 No
12、rmative References2.1 These requirements are based upon the Standard for Low Voltage Switchgear and Controlgear, Part4: Contactors and Motor-Starters, IEC Publication 947-4-1.2.2 Prior to conducting the verification tests, the manufacturer shall provide for review Type 2coordination charts (that is
13、coordination of the motor controller, thermal overload relay, and short circuitprotective device). When the optional tests detailed in Discrimination Between Overload Relay and ShortCircuit Protective Devices, Section 18, are also to be conducted, graphs showing the crossover point ofthe mean curves
14、 representing the time-current characteristics of the overload relays and the short circuitprotective devices shall be provided.3 Definitions3.1 For the purpose of this Outline of Investigation, the following definitions apply. The definitions includedin 3.9 3.11, 3.13, and 3.16 are from IEC 947-1,
15、Standard for Low Voltage Switchgear and Controlgear,Part 1: General Rules.3.2 CONTACTOR An electromechanical device rated in horsepower, full load-locked rotor current(FLA LRA), or both, capable of repeatedly interrupting a motor load under normal conditions includingoverload conditions.3.3 CO SHOT
16、(CLOSING) Closing the contacts of the contactor or circuit breaker on the shortcircuit fault. The contactor or circuit breaker is in the open position prior to the initiation of the fault. Thiscondition is accomplished by the external switch (the fixed switch of the test station) being closed during
17、the closing of the contactor or circuit breaker.3.4 DISCRIMINATION BETWEEN OVERLOAD RELAY AND SHORT CIRCUIT PROTECTIVE DEVICE Verification of the performance of the thermal overload relays of the starters and associated shortcircuit protective devices (SCPD) at currents below and above the intersect
18、ion of their respective time/current characteristics and the corresponding Type 2 coordination.NOVEMBER 15, 2006SUBJECT 508E4UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM UL3.5 IP2X An enclosure which is protected against solid foreign objects
19、 of 12.5 mm (0.50 inch) orgreater in diameter as determined by the use of an object probe having a diameter of 12.5 mm and arounded spherical end. The object probe shall not penetrate the enclosure when pushed through anyopening in the enclosure with a force of 30 N 10 percent (6.74 lbf).3.6 Iq The
20、high capacity short circuit fault current assigned by the manufacturer (in IEC terminology,rated conditional short circuit current). Any short circuit fault current assigned by the manufacturer thatexceeds r is denoted as Iq.3.7 MOTOR CONTROLLER A contactor or starter.3.8 O SHOT (WITHSTAND) Closing
21、the short circuit fault on the contactor. The contactor is in theclosed position prior to the initiation of the fault. This condition is accomplished by the use of theexternal switch (the fixed switch of the test station).3.9 POWER-FREQUENCY RECOVERY VOLTAGE The recovery voltage after the transient
22、voltagephenomena have subsided.3.10 PROSPECTIVE CURRENT The current which flows in the circuit when each pole of thecontroller or fuse is replaced by a conductor of negligible impedance.3.11 PROSPECTIVE PEAK MAKING CURRENT The peak value of the prospective current wheninitiated under specified condi
23、tions. (Equivalent to peak value of fault current).3.12 r The standard short circuit fault current (in IEC terminology, Prospective Current)corresponding to the motor full load ampere rating (in IEC terminology, rated operational current).3.13 RECOVERY VOLTAGE For a single-pole service, the voltage
24、which appears across theterminals of a pole of a switching device or a fuse after the breaking of the current. This voltage is to bemeasured at one time or in two successive intervals of time, one during which a transient voltage exists,followed by a second one during which the power-frequency volta
25、ge or the steady-state recoveryvoltage alone exists. For a multipole device, it is the phase-to-phase voltage across the supply terminalsof the device.3.14 SCPD Abbreviation for short-circuit protective device.3.15 STARTER A combination of a contactor and a thermal overload relay.3.16 TRANSIENT RECO
26、VERY VOLTAGE The recovery voltage during the time in which it has asignificant transient character.3.17 TYPE 2 COORDINATION Under short-circuit conditions, the controller shall not result indanger to persons or the installation, and after the short-circuit test the controller shall be capable offurt
27、her use. The risk of contact welding is recognized, in which case the manufacturer shall indicate themeasures to be taken regarding maintenance of the equipment.NOVEMBER 15, 2006 SUBJECT 508E 5UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM UL4
28、General4.1 When a value for measurement is followed by a value in other units in parentheses, the first statedvalue is the requirement.CONSTRUCTION5 General5.1 For the purpose of Type 2 coordination, the motor controller, with or without thermal overload relay,shall comply with the applicable requir
29、ements in the Standard for Industrial Control Equipment, UL 508.5.2 The thermal overload relay, when not part of the motor controller, shall comply with the applicablerequirements in the Standard for Industrial Control Equipment, UL 508.5.3 A short circuit protective device (SCPD) for motor controll
30、ers other than a starter that is provided withshort circuit protective devices (in IEC terminology Protected Starter) and discrete component typecombination motor controllers shall be:a) Nonrenewable branch circuit cartridge fuses complying with the requirements in theStandard for High-Interrupting-
31、Capacity Fuses, Current Limiting Types, UL 198C; the Standardfor Class K Fuses, UL 198D; the Standard for Class R Fuses, UL 198E; or the Standard forD-C Fuses for Industrial Use, UL 198L; orb) Nonrenewable branch circuit cartridge fuses complying with the requirements in the UL 248series of standard
32、s; orc) Inverse time circuit breakers complying with the requirements in the Standard for Molded-Case Circuit Breakers, Molded-Case Switches, and Circuit Breaker Enclosures, UL 489.5.4 In reference to the requirements in 5.3, an instantaneous type circuit breaker (magnetic only) is ableto be used as
33、 a short-circuit protective device when the specific combination of the starter andinstantaneous type circuit breaker comply with the requirements for combination motor controllers asoutlined in the specific part for combination motor controllers in the Standard for Industrial ControlEquipment, UL 5
34、08.5.5 A circuit breaker which is provided with current limiters that have been previously evaluated is able tobe employed for branch circuit protection when the current limiters comply with the Short Circuit Test forprotective devices as specified in the Standard for Industrial Control Equipment, U
35、L 508.NOVEMBER 15, 2006SUBJECT 508E6UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULPERFORMANCE6 Enclosure Tests6.1 An enclosed-type motor controller shall be tested within the same enclosure with which it had beenpreviously investigated.6.2 A
36、n open-type motor controller is to be tested in the smallest size enclosure specified by themanufacturer. The enclosure size shall not be larger than the size of the enclosure in which the controllerhad been previously investigated. The enclosure cover is to be held closed only by the simplest latch
37、ingmechanism and securement means (i.e. the least provisions for pressure relief) or, when the endapplication and enclosure construction have been determined, by the intended latching mechanism andsecurement means.7 Conductors, Conduit, and Terminal Torque7.1 The size, length, insulation rating, and
38、 type of conductors as well as the length of the conduit shall bethe same as specified under the Short Circuit Test in the Standard for Industrial Control Equipment, UL508.7.2 The terminal torque shall be as marked on the motor controller.8 Selection of Heater Elements8.1 For each controller that is
39、 provided with a thermal overload relay, the heater elements selected forthe tests shall consist of the minimum and maximum resistance heaters. When the construction andmaterial of the intermediate resistance heater elements are different from those of the minimum andmaximum resistance heaters, an i
40、ntermediate resistance heater among each group with differentconstruction shall also be selected for tests.9 Calibration of Test Circuits9.1 The test circuits for both r and Iq fault currents shall be calibrated as specified under Calibrationof Test Circuits in the Standard for Industrial Control Eq
41、uipment, UL 508.NOVEMBER 15, 2006 SUBJECT 508E 7UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM UL10 Power Factor Requirements10.1 The power factor of the test circuits shall be in accordance with Table 10.1. Table 10.1 also providesthe values o
42、f time-constant for DC Circuits. The power factor of a polyphase circuit is the mean value ofthe power factors of each phase.Table 10.1Values of power factors and time-constants corresponding to test currentsTest current IaPower factor Time-constant(A) (ms)I 1,500 0.95 51,500 I 3,000 0.9 53,000 I 4,
43、500 0.8 54,500 I 6,000 0.7 56,000 I 10,000 0.5 510,000 I 20,000 0.3 1020,000 I 50,000 0.25 1550,000 I 0.2 15a r or Iq.10.2 The difference between the mean value and the maximum and minimum values of the power factorsin the different phases shall remain within 0.05.11 Ground Fuse (Link) Requirements1
44、1.1 For prospective short circuit fault currents of 1500 A or more, the metal enclosure is to be connectedthrough a fusible element consisting of a copper wire 0.8 mm (0.031 inch) in diameter and at least 50 mm(1.97 inch) long, or a 30-A non-time delay cartridge fuse which has been evaluated and fou
45、nd to beequivalent to a 0.8 mm thick, 50 mm long copper wire for the detection of ground fault, to the electricalsupply live pole determined least likely to strike to ground. The connection is to be made to the load sideof the limiting impedance by a 5.3 mm2(No. 10 AWG) copper wire that is 1.22 1.83
46、 m (4 6 feet) long.11.2 In reference to the requirement in 11.1, for a minimum prospective current of 1000 A, the fusibleelement consists of a copper wire 0.6 mm (0.023 inch) in diameter and at least 50 mm (1.97 inch) long.NOVEMBER 15, 2006SUBJECT 508E8UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURT
47、HER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM UL12 Recovery Voltage12.1 When the SCPDs consist of branch circuit fuses, the recovery voltage shall be at least equal to therated voltage, as required in the Short Circuit Test requirements in the Standard for Industrial ControlEquipment, UL 5
48、08.12.2 When the SCPDs consist of circuit breakers, the value of the power-frequency recovery voltage shallbe 1.05 times the value of the rated voltage. The power-frequency recovery voltage is the circuit breakerrecovery voltage.12.3 The value of 1.05 times the rated operational voltage for the powe
49、r-frequency recovery voltage (See12.2) covers the effects of the variations of the system voltage under normal service conditions. Theapplied voltage is to be increased as required to achieve the specified recovery voltage. The prospectivepeak making current shall not be exceeded without the consent of the manufacturer. The upper limit ofthe power-frequency recovery voltage is able to be increased with the agreement of the manu
