Sidactor Protection Thyristor Products Page 38 SIDACtor Protection Thyristor Products

SIDACtor Protection Thyristors 2017 Littelfuse, Inc. Specifications are subject to change without notice. Revised: 02/23/17 Current Limiting Protector Test The purpose of the Current Limiting Protector Test is to determine if the EUT allows an excessive amount of current flow under power fault conditions. During this test, the EUT is connected to a circuit equivalent to that shown in Figure 3.3 above with a 1.6 A Type MDQ fuse or MDL 2.0A fuse as the wiring simulator. If the EUT draws enough current to open the fuse, then the acceptable time/current criteria have not been met, and external current limiting protectors must be specified for use with that quipment in the manufacturer's documentation. This test is conducted at 2.2 A, 2.6 A ,3 A, 3.75 A, 5 A, 7 A, 10 A, 12.5 A, 20 A, 25 A, and 30 A for 15 minutes at each subsequent value until the equipment interrupts the current or reduces it to less than 50 mA. IF the wiring simulator opens, the EUT does not meet the criteria. 100 70 1000 100 10 1 0.1 1 2 3 4 5 6 10 7 20 30 40 50 60 ACCEPTABLE REGION UNACCEPTABLE REGION ACCEPTABLE REGION LIMITS CURRENT MAXIMUMTIME (A) 60 30 7 3 (s) 0.013 0.065 2.5 900 0.01 Current (Amperes) TIME (Seconds) Figure 3.4: Time-current characteristics of the external current-limiter indicator. Short-circuit Test Lightning Protection tests for Equipment located in high exposure locations (Port Type 3 & 5) Criteria for Equipment containing agreed primary protectors Criteria for Equipment with Integrated Primary Protectors (EIPP) In addition to the AC Power Fault and Current Limiter Tests, equipment must also pass a Short-circuit Test to comply with GR 1089. During this test, a short-circuit condition is applied to the following Tip and Ring appearances for 30 minutes while the EUT is powered and under operating conditions: Tip-to-Ring, Tip-to-Ground with Ring open circuit Ring-to-Ground with Tip open circuit Tip- and Ring-to-Ground simultaneously for 30 minutes At no time will the short circuit impedance exceed 1-ohm. For equipment with more than one twisted pair, the short circuit is applied to all twisted pair simultaneously. To comply with the short circuit test, the EUT must function normally after the short-circuit condition is removed, and a fire or electrical safety hazard may not be present. The equipment shall not require manual intervention to restore service. The surge generator for high exposure risk environments shall be capable of delivering 4kV into an open circuit and capable of delivering 500A into a short circuit, with a 10x250 S waveshape. The switching voltage of the primary protector must first be determined before applying this 10x250 surge to the EUT OR the EUT must have a surge withstand capability adequate to survive these severe events. For a EUT that is preceded by a 3 mil carbon block, which is typically a worse case scenario, the maximum let-through voltage this carbon block allows would be 1 kV. Under these conditions, the EUT would see a 1 kV open circuit voltage and 125A short circuit surge event. Some primary protectors contain series elements that would further reduce the current delivered into the EUT. Therefore, the primary protector characteristics must be determined before this high exposure test is conducted. Once it surge characteristics are determined, then this 10x250 surge event is applied 10 at the allowed let- through voltage and current levels. This generic requirements document contains a section for customer premises and non-CO type facilities equipment that are protected by a known defined primary protector other than 3-mil blocks. This section contains four different categories for agreed primary protection. The categorization will then reduce the open circuit voltage used for lightning and power fault testing as previously defined in first and second level lightning and ac power fault tables. Please see Littelfuse for more details on this section. This GR also contains a section for equipment that has integrated primary protection on the ports with direct connections to the OSP. Please contact Littelfuse, Inc. for more details on this section. Lightning surge Tests for Severe Climatic Conditions For Type 3 and 4 ports that interface with 8 or fewer OSP conductors, a more severe lightning surge event is applied. See Table 3.13 below. Surge Level Surge Voltage (V PK ) Current Waveshape ( s) Surge Current per Conductor (A) Repetitions Each Polarity Test Connections 1 st 3000 10x250 2000 1 T to R; single pair only 2 nd 5000 8x20 20000 1 T to R; single pair only Table 3.13: Severe Climatic Surge Test Regulatory Requirements (continued)

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