Sidactor Protection Thyristor Products Page 37 SIDACtor Protection Thyristor Products

SIDACtor Protection Thyristors 2017 Littelfuse, Inc. Specifications are subject to change without notice. Revised: 02/23/17 AC Power Fault Tests Power companies and telephone operating companies often share telephone poles and trenches; therefore, network equipment is often subjected to the voltages seen on power lines. If direct contact between the telephone line and the primary power line occurs, the operating company's network equipment may see as much as 600 V rms for five seconds, by which time the power company's power system should clear itself. If direct contact occurs with the secondary power line, voltages will be limited to 277 V rms; however, these voltages may be seen indefinitely because the resultant current may be within the operating range of the power system and the power system will not reset itself. Another risk involved with power lines is indirect contact. Because of the large magnetic fields created by the currents in the power lines, large voltages may be induced upon phone lines via electro-magnetic coupling. In this instance voltages should be limited to 1000 V peak and 600 V rms using primary protectors, while the current will be limited by the current-carrying capacity of the 24-gauge wire. First Level AC Power Fault Criteria Second Level AC Power Fault Criteria Table 3.12: Second Level AC Power Fault Test (and Intra- building 2nd level) Test Applied Voltage, 60 Hz (V RMS ) Short Circuit Current per Conductor (A) Duration Primary Protectors Test Connections 1 (Note 1) 50 0.33 15 min Removed A 2 (Note 1) 100 0.17 15 min Removed A 3 (Note 1) 200, 400, 600 1A at 600V 60 applications, 1s each Removed A 4 (Note 4) 1000 1 60 applications, 1s each In place B 5 (Note 2) N/A 60 applications, 5s each Removed N/A 6 (Note 3) 600 0.5 30 s Removed A 7 (Note 3) 440 2.2 2 s Removed A 8 (Note 3) 600 3 1.1 s Removed A 9 (Note 3) 1000 5 0.4 s In place B Table 3.11 presents test conditions for the First Level AC Power Fault Test. The EUT is required to pass operationally. Table 3.12 below presents test conditions for both customer premises and non-customer premises equipment. (Note that test conditions 1, 3, and 4 may be omitted if the EUT has previously met UL 60950-1.) Notes: 1. For EUT containing secondary voltage limiting and current limiting protectors, tests are to be performed at the indicated voltage(s) and repeated at a reduced voltage and current just below the operating threshold of the secondary protectors. 2. Test 5 simulates a high impedance induction fault. For specific information, contact Littelfuse, Inc. 3. Sufficient time may be allowed between applications to preclude thermal accumulation. 4. This test is intended to establish compatibility of the EUT with the primary protector. The maximum current is limited to 1 A rms as in Test 3, but the voltage is increased to 1,000 V to permit operation of the protector. Sufficient time may be allowed between applications to preclude thermal accumulation. Test (Notes 1, 2) Applied Voltage, 60 Hz (V RMS ) Short Circuit Current per Conductor (A) (Note 4) Duration Test Connections 1 (Note 5) 120, 277 25 15 min A 2 600 60 5 s A 3 600 7 5 s A 4 600 2.2A at 600 V 15 min A 5 (Note 3) N/A N/A 15 min N/A Notes: 1. Primary protectors are removed for all tests. 2. For EUT containing secondary voltage limiting and current limiting protectors, tests are to be performed at the indicated voltage(s) and repeated at a reduced voltage and current just below the operating threshold of the secondary protectors. 3. Test 5 simulates a high impedance induction fault. Specific information regarding this test is available upon request. 4. These tests are repeated using a short-circuit value just below the operating threshold of the current limiting device, or, if the EUT uses a fuse as current limiting protection, the fuse may be bypassed and the short circuit current available adjusted to 135 percent of the fuse rating. 5. Intra-building, second level power fault test uses test condition 1 only. The applied voltage is at 120 V rms only. Table 3.11: First Level Power Fault Equipment Tip Wiring Simulator Ring Chassis Ground 20 Variable 60 Hz ac Voltage Source 0-600 V (A) Metallic AC Equipment Ground (Green Wire Ground) Equipment Tip Ring Chassis Ground 20 Wiring Simulator 20 Variable 60 Hz ac Voltage Source 0-600 V (B) Longitudinal AC Equipment Ground (Green Wire Ground) Wiring Simulator Figure 3.3: Second Level AC Power Fault and Current Limiter Connection Regulatory Requirements (continued)

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