Sidactor Protection Thyristor Products Page 65 SIDACtor Protection Thyristor Products

SIDACtor Protection Thyristors 2017 Littelfuse, Inc. Specifications are subject to change without notice. Revised: 02/23/17 Overvoltage Test Procedures Overvoltage Test Compliance Use the following criteria when applying the overvoltage tests presented in Table 3.53. 1. Test Set-up-Equipment is to be mounted as it is intended to be used. Tests may be conducted on either the equipment as an assembly, individual subassemblies, or a partial assembly containing those components which may be exposed to an overvoltage condition. 2. Indicators-Before testing, two single pieces of cheesecloth are to be wrapped tightly around the assembly, subassembly, or partial assembly. The cheesecloth acts as an indicator for conditions that may result in fire. 3. Line Cords-Equipment with a removable telecommunications line cord is to be connected to the test circuit with a line cord having 0.4 mm (26 AWG) or larger copper wire conductors and not more than 1 total resistance. 4. Functional Circuitry-UL mandates that functional circuitry must be used for each overvoltage test conducted. This allows repair or replacement of damaged circuitry before subsequent testing. Alternatively, separate samples may be used for each test. 5. Wiring Simulators-A wiring simulator is used to indicate whether the maximum I2t imposed upon telecommunications wiring has been exceeded. For Tests 1 and 5, a wiring simulator is to be used unless the equipment is specified for use with a suitable secondary protector or a secondary protector simulator. The wiring simulator can consist of one of the following: a. 50 mm length of 0.2 mm (32 AWG) bare or enameled solid copper wire (for test condition 1 and 5) b. Type MDL-2A fuse (for test condition 1 and 5) or equivalent c. Current probe used with a 300 mm length of 0.5 mm (24 AWG) copper wire (for test condition 1 only) Note: Test conditions 2, 3, and 4 do not require the use of a wiring simulator or a secondary protector simulator. Any secondary protection simulators used in Tests 1 and 5 should be similar to the test fuse used in UL 497A, " Standard for Secondary Protectors for Communications Circuits ." Equipment is deemed compliant if each of the following conditions is met during test: Absence of ignition or charring of the cheesecloth indicator (Charring is deemed to have occurred when the threads are reduced to char by a glowing or flaming condition.) Wiring simulator does not open during test condition 1 or 5 For test condition 1, presented in Table 3.53, the integral I 2 t measured with a current probe is less than 100 A2s. After completion of the overvoltage tests, equipment must comply with either the Dielectric Voltage-withstand Test requirements with all components in place or the Leakage Current Test requirements. Special Considerations Regarding the SIDACtor Device and UL 60950-1 Coax cable distribution Systems The epoxy used for SIDACtor devices is UL recognized and the encapsulated body passes UL 94V-0 requirements for flammability. The only specific requirements of UL 60950-1that pertain to the SIDACtor device itself are the impulse test and the mandate that components be UL recognized. All other UL 60950-1 requirements pertain to the equipment being evaluated. The insulation between the primary circuit and the terminal or lead provided for the connection of a cable distribution system shall pass either: 1) the voltage surge test of UL 60950-1 Clause 7.4.2 for equipment intended to be connected to outdoor antennas; or 2) the impulse test of UL 60950-1 Clause 7.4.3 for equipment intended to be connected to other cable distribution system If the EUT is intended for connection to both an outdoor antenna and another cable distribution system, it shall pass the tests of both UL 60950-1 Clause 7.4.2 and UL 60950-1 clause 7.4.3. The following conditioning pulses are applied between: 1) the connection points for the cable distribution system all joined together AND 2) the supply circuit terminals joined together with the main protective earthing terminal At the conclusion of these surges, the electric strength tests are conducted. All components between the connection points for the cable distribution system and the protective earthing terminal are disconnected before these tests are applied. UL 60950-1 Clause 7.4.2 UL 60950-1 Clause 7.4.3 10 kV V 15 M 1 k 1 nF EUT 100M .1 M The 10 kV surge generator as defined in IEC 60065 (example shown in figure 3.22) is used to apply 50 surges to the EUT. These surges are applied at a maximum rate of 12 pulses per minute. 1) 10 10x700 S voltage waveshape surge event with an open circuit value of 5 kV and a 5x310 current waveshape with a short circuit value of 125A for power-fed repeaters 2) 10 10x700 S voltage waveshape surge event with an open circuit value of 4 kV and a 5x310 current waveshape with a short cir 100A for all other equipment FIgure 3.22 IEC 60065 Surge Generator Regulatory Requirements (continued)

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