Ref No: Date: February 8, 1995 INDUSTRIAL CONTROL EQUIPMENT NO. 2

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1 Ref No: Date: February 8, 1995 INDUSTRIAL CONTROL EQUIPMENT NO. 2 To: Manufacturers of Industrial Control Equipment Subject: Publication of Technical Information Letter (T.I.L.) No D-21 on Interim Certification Requirements for Control Devices Rated at More Than 1500 V But Not More Than 7200 V for Electric Motors Background and Rationale The Scope of CSA Standard C22.2 No was limited to 5000 V ac, however when the Standard was revised in order to harmonize it with Standard UL 508, Industrial Control Equipment, the Scope was limited to 1500 V ac. In response to the needs of the industry, CSA has developed requirements for high voltage motor controllers based on the 1973 edition of CSA Standard C22.2 No 14 and UL Standard UL 347, High Voltage Industrial Control Equipment. The requirements are covered in the attached T.I.L. No D-21. The Scope of this T.I.L. represents an increase in the maximum voltage rating to 7200 V from 5000 V. Direction Applications should include the full company name, address, the location of each factory and a reference CSA file number(s), as applicable. When an application is received, customers will be advised of the quantity and type of sample required for evaluation. Applications and Inquiries If you wish to make an application, please contact one of the CSA Offices or CSA Network Partners listed below. TILDL1/DL027/1/dw Page 1 of 8

2 CSA Offices Telephone Telefax Moncton (506) (506) Montreal (514) (514) Rexdale (416) (416) Rexdale (Standards Sales) (416) (416) Winnipeg (204) (204) Edmonton (403) (403) Vancouver (604) (604) Hong Kong (852) (852) Japan (81) (81) CSA Network Partners Pacific Rim (and Far East): SAQAS (Australia) (61) (61) CCIC (China) (86) (86) HKSTC (Hong Kong) (852) (852) BIS (India) (91) (91) JQA (Japan) (81) (81) A-PEX (Japan) (81) (81) I-TEC (Japan) (81) (81) SIRIM (Malaysia) (60) (60) SANZ (New Zealand) (64) (64) SISIR (Singapore) (65) (65) KAIT (South Korea) (82) (82) CTS (Taiwan) (886) (886) Europe (and Middle East): OVE (Austria) (43) (43) LCIE (France) (33) (33) UTE (France) (33) (33) N.V. KEMA (Netherlands) (31) (31) VDE-PZI (Germany) (49) (49) PCBC (Poland) (48) (48) SII (Israel) (972) (972) IMQ (Italy) (39) (39) SEMKO AB (Sweden) (46) (46) SEV (Switzerland) (41) (41) BSI (U.K.) (44) (44) BSI Testing (U.K.) (44) (44) North America: CCL (Utah) (801) (801) PSE (California) (714) (714) PSE (Florida) (813) (813) South America: BV Bureau Veritas (55) (55) TILDL1/DL027/2/dw Page 2 of 8

3 TECHNICAL INFORMATION LETTER NO D-21 Certification and Testing Division Product Group: Industrial Control Date: February 8, 1995 Issued By: Jim Walsh/Nino Mancini EQUIPMENT: ITEM: Industrial Control Equipment Interim Certification Requirements for Control Devices Rated at More Than 1500 V But Not More Than 7200 V, for Electric Motors STANDARD NOS: CAN/CSA C22.2 No 0-M91 - General Requirements - Canadian Electrical Code, Part II CAN/CSA C22.2 No 14-M91 - Industrial Control Equipment 1. Scope This Technical Information Letter (T.I.L.) contains construction and test requirements for control devices rated more than 1500 V but not more than 7200 V, for starting, stopping, regulating, controlling, or protecting electric motors, and intended to be installed and used in nonhazardous locations in accordance with the Rules of the Canadian Electric Code, Part I. 2. General Requirements 2.1 The requirements of this T.I.L. shall be used in conjunction with the requirements of CSA Standard C22.2 No 14-M91 when certifying the equipment. 2.2 The requirements of this T.I.L. shall take precedence over those of the relevant Part II Standard having similar intent. 3. Definitions Controller - means a device or a group of devices for governing in some predetermined manner the electric power delivered to the apparatus to which it is connected. Class E1 high-voltage controller - means a controller rated over 2,000 volts but not over 7200 volts and employing its contacts for both starting the motor and interrupting short circuits. TILDL1/DL027/3/dw Page 3 of 8

4 Class E2 high-voltage controller - means a controller rated over 2,000 volts but not over 7200 volts and employing its contacts for starting the motor and fuses for interrupting short circuits. 4. Construction - Enclosure Doors and Covers 4.1 In high-voltage equipment, barriers shall be provided if necessary to prevent access to any live high-voltage parts, including insulated conductors located in enclosures containing low voltage parts and wiring. Rationale: Insulating barriers are required to prevent accidental contact of live parts that may result in shock hazard. The requirements appear in Clause of the 1973 edition of CSA Standard C22.2 No Controllers of the draw-out type shall comply with the requirements of Clause 4.1 with the draw-out unit removed from the cubicle. Automatic shutters or the equivalent shall be provided to close up any openings intended to accommodate the draw-out high-voltage stab contacts. Rationale: Draw-out type controllers can be removed without the use of a tool. Therefore, no live parts that may result in an shock hazard should become accessible after the removal of the controllers. The requirements appear in Clause of the 1973 edition of CSA Standard C22.2 No Doors providing access to high-voltage compartments and high-voltage fuses if used, shall be mechanically interlocked with the isolating means to permit opening the door only when all high-voltage parts are disconnected from the highvoltage source by a spacing of two inches or by equivalent insulation. There shall be visible proof when the door is open to clearly show that such disconnection has been made. Doors of compartments containing high-voltage components auxiliary to the controller (but not including fuses), and for which mechanical interlocking of doors is impracticable shall be bolted closed and provided with a warning sign. Rationale: The unbolted door of an electrical compartment for high-voltage wiring can be easily opened, resulting in the exposure of live parts. This could cause an electric shock for a user. Therefore, means should be provided to disconnect all high-voltage parts when the door is opened. The requirements appear in Clause of the 1973 edition of CSA Standard C22.2 No 14. Note: The requirements for visible proof specified in Clause 4.3 will be considered to be fulfilled if a clearly visible target is provided and is directly connected without auxiliary mechanisms to the shutter covering any bare live stab contacts. 4.4 Mechanical or electrical interlocking shall be provided to ensure that the contactor high-voltage contacts are open before the disconnecting means is opened unless the disconnecting means is a load break switch. Interlocking (either electrical or mechanical) also shall be provided to ensure that the contactor high-voltage contacts are open before the disconnecting means is closed. TILDL1/DL027/4/dw Page 4 of 8

5 Rationale: Contactor high-voltage contacts may be damaged, if they are not open before the disconnecting means is closed. Mechanical or electrical interlocking will prevent the occurrence of this problem. The requirements appear in Clause of the 1973 edition of CSA Standard C22.2 No Spacings Unless as permitted in Clause 4.5.2, spacings through air or oil, and spacings over surfaces in air or oil shall be not less than the values shown in Table 1. Rationale: Spacings between live parts and non-current-carrying metal parts for voltages more than 1500 V but not more than 7200 V are quite different from those for electrical circuits operating at 1500 V or less. The values shown in Table 1 provide the minimum spacings that will prevent electrical failures and shock hazard For components that are rated at 1500 V or less, spacings shall be in accordance with CSA Standard C22.2 No 14-M91. Rationale: Minimum electrical spacings for voltages at 1500V or less should be less than those for more than 1500 V. The requirement covers components that operate at 1500 V or less The high-voltage circuit of a controller operating at the nominal voltage range from 5000 V to 7200 V shall be capable of withstanding the impulse withstand test of Clause Tests 5.1 General The general test requirements of CSA Std. C22.2 No. 14-M91 shall be applicable. In addition to the tests required by that Standard, the additional tests of the following clauses 5.2 to 5.6 inclusive shall be applicable. 5.2 Overload For air break ac contactors in E2 controllers, the contactor shall be capable of interrupting six times the current corresponding to its horsepower rating at rated voltage, 50 percent power factor maximum and rated frequency. The test cycle shall be 2 (CO) unit operations at two-minute intervals followed in 30 minutes by 2 further (CO) unit operations at two-minute intervals or a cycle of equivalent severity. The controller structure shall be grounded through a 3-ampere fuse. Immediately after the above total test cycle the contactor shall be capable of carrying rated continuous current without replacement or adjustment of any parts. Any indication of failure to interrupt, or contact welding during test, or blowing of the 3-ampere fuse to ground, shall be classified as a failure. TILDL1/DL027/5/dw Page 5 of 8

6 Note: The requirements appear in Clause of the 1973 edition of CSA Standard C22.2 No Endurance Contactors shall be tested without load for 10,000 operations at the rate specified by the manufacturer. There shall be no mechanical failure of the contactor during this test. Note: The requirements appear in Clause of the 1973 edition of CSA Standard C22.2 No Short Circuit A Class E high-voltage controller shall be capable of interrupting its rated short circuit current, including any dc components in the test circuits during the test cycles specified in Clause Remarks: (a) (b) For the test specified in Clause 5.4.1, the controller structure is to be grounded through a 3-ampere fuse. Class E2 controllers are to be tested with fuses of the highest current rating for which the controller is intended to be used For a Class E high-voltage controller, the test cycle for the short-circuit test specified in Clause shall consist of a specified number of unit operations at stated intervals. A unit operation shall consist of a closing followed immediately by an opening of the circuit without purposely delayed action as designated by the letters "CO", signifying closing-opening. The test cycle shall be as follows: (a) (b) For a Class E1 controller: three (CO) unit operations at two minute intervals; and For a Class E2 controller: three (CO) unit operations separated by the interval required to renew the fuses, inspect contacts and replace them, if necessary At the end of any of the test cycles specified in Clause a Class E high-voltage controller shall comply with the following requirements: (a) General. A controller shall perform without the emission of flame from its enclosure. Blowing of the 3-ampere fuse between the controller enclosure and ground shall be considered a failure. On Class E2 controllers, welding of contact tips under the specified test duty cycle shall not be considered a failure. Remarks: On Class E2 controllers, it is not necessary for the contact tips to remain closed during the interrupting cycle. (b) Mechanical. The controller, with the exception of the blowing of fuses, shall be in substantially the same mechanical condition as at the beginning of the test. TILDL1/DL027/6/dw Page 6 of 8

7 (c) Electrical. The controller shall be capable of withstanding rated voltage in the open position and of carrying rated current at rated voltage for a limited time but not necessarily without exceeding the rated temperature rise. Remarks: After a test cycle at or near its interrupting rating, it is not to be inferred that the controller can again meet its interrupting rating without minor repairs, such as replacement of contacts. Note: The requirements appear in Clause to of the 1973 edition of CSA Standard C22.2 No Impulse Withstand A previously untested control shall be used. The voltage shall be full-wave 1.2 x 50 µs impulses in accordance with ANSI/IEEE Standard 4, and having a crest value in accordance with Table 2. Three positive and three negative impulses shall be applied. The minimum interval between pulses shall be 1 s. The equipment shall withstand the voltage impulse without breakdown in accordance with Clause Dry-type core and coil assemblies, such as reduced-voltage-starting reactors and autotransformers and control-circuit transformers, may be disconnected for this test The sequence of tests shall be as follows: (a) (b) (c) Test 1 - With the controller bus installed, the isolating means closed, the high-voltage motor circuit fuses (in case of Class E2 controllers) and control circuit fuses in place, and the contact in the open position, the test voltage as shown in Table 2 shall be applied between each electric circuit and grounded metal parts, and between each principle electric circuit and all other principle circuits, except that the impulse test need not be applied across the open tip gap of the contactor. Test 2 - Test 1 shall be repeated except that the contactor shall be closed. Test 3 - With the isolating means open, the impulse voltage shown in Table 2 shall be applied in each phase individually between the contacts of the isolating means across the isolating gap. If the isolating means has provision for automatically grounding its load side when in the fully opened position, the test voltage shall be the value specified under Tests 1 and 2. Note: The requirements appear in Section 32 of UL Standard UL 347 "High Voltage Industrial Control Equipment". 5.6 Dielectric Withstand For high voltage components rated 1501 to 7200 V, the Dielectric Withstand Test shall be conducted as required in clause 6.8 of C22.2 No. 14-M91. The applied test voltage shall be 2 1/4 times the rated voltage plus 2000 volts. TILDL1/DL027/7/dw Page 7 of 8

8 Voltage Rating 1,501-2,500 TABLE 1 (See Clause 4.5.1) MINIMUM SPACINGS FOR LIVE PARTS Minimum Spacing - Inches Between Bare Live Parts of Opposite Polarity and Between Bare Live Parts and Grounded Metal Parts Other Than the Enclosure Through Air 1.00 Through Oil 0.75 Over Surface in Air 2.00 Over Surface in Oil 1.00 Between Bare Live Parts and the Walls of Metal Enclosures Including Fittings For Conduit or Armoured Cable Through Air or Oil 2.00 Over Surface In Air or Oil ,501-7, Note: A metal piece attached to the enclosure is considered to be a part of the enclosure if deformation of the enclosure is liable to reduce spacings between the metal piece and bare live parts. TABLE 2 (See Clause 5.5) IMPULSE WITHSTAND TEST - CREST VOLTAGES a Impulse Test Voltage, Crest Kilovolts Tests 1 and 2 Test 3 Level A a Level B Level A a Level B The Level A test voltages may be used if appropriate to the degree of exposure to lightning overvoltage, the type of system grounding, and the type and location of surge arrestor on the source side. TILDL1/DL027/8/dw Page 8 of 8