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Standard Overview Products Used in Testing Related Compliance Standards

Standard Overview
UL 943 covers ground-fault circuit-interrupters intended for use only in alternating-current circuits wherein one of the wires is grounded in accordance with the National Electrical Code. Devices complying to UL 943 are intended for use on 120 Vac or 120/240 Vac, 60 Hz circuits. These requirements do not cover ground-fault circuit-interrupters intended for use in circuits served by a transformer having windings wholly insulated from each other. A ground-fault circuit-interrupter as covered by these requirements is a device whose function is to interrupt the electric circuit to the load when a fault current to ground exceeds some predetermined value that is less than that required to operate the overcurrent protective device of the supply circuit.

UL 943 provides requirements for ground-fault circuit-interrupters for use in accordance with the electrical installation codes of Canada, Mexico, and the United States. At present there is no IEC Standard for ground-fault circuit-interrupters for use in accordance with these codes. Therefore, this Standard does not employ any IEC Standard for base requirements.

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UL 1414 Section 16: Impulse Voltage Test
16.1 Twelve samples of a capacitor are to be tested as described in 16.2 and 16.3. As a result of the tests, there shall not be permanent breakdown or flashover. 16.2 Each capacitor is to be mounted by the leads in a fixed position with the capacitors randomly oriented in any end-use configuration not prohibited by the physical construction of the capacitor. The free length of the leads is to be at least 1 in (25.4 mm) unless the samples are provided with shorter leads. 16.3 Each individual capacitor is to be subjected to a maximum of 24 impulses of the same polarity. The time between impulses shall not be less than 10 s. 16.4 The peak value of the impulse voltage (Vp) is to be 4 kVdc for Class X1 capacitors. 16.5 The peak value of the impulse voltage (Vp) is to be 8 kVdc for Class Y1 capacitors. 16.6 The peak value of the impulse voltage (Vp) is to be 5 kVdc for Class Y2 capacitors. 16.7 When any three successive impulses are shown by the oscilloscope to have a waveform indicating that no self-healing breakdowns or flashovers have taken place in the capacitor, no further impulses are to be applied, and the capacitor complies with the requirement. When all 24 impulses have been applied to the capacitor, and three or more of the waveforms indicate that no self-healing or flashovers have occurred, the capacitor complies with the requirement. When less than three waveforms are of the required waveform, the capacitor does not comply with the requirement. Exception: When the waveform has a dampened oscillation, the peak-to-peak voltage (VPP) of the oscillation shall not be greater than 10 percent of the peak voltage (VP) of the impulse. 16.8 The waveform is to be determined by the circuit components in the test circuit. Figure 16.2 illustrates the circuit to be used in performing this test. The parameters of the components in the test circuit are to be in accordance with Table 16.1.
UL 1449: Surge Protective Devices (SPD)
UL's safety and performance standard for Surge Protective Devices (SPD), formerly known as Transient Voltage Surge Suppressors (TVSS), is UL 1449. This standard applies to end-users, manufacturers, and specifiers. As a generalization, UL addresses electrical product safety in areas that involve a risk of fire, electric shock, or injury to persons. UL verifies the safe operation of SPDs through a listing or component recognition process including a series of stringent destructive and non-destructive tests. These ensure safe operation during normal operation and at the unit's end of life. End-of-life characteristics are particularly important because SPDs are placed in harm’s way and can affect the rest of the electrical distribution system. Areas of interest include fault current testing, thermal issues, touch-safety, etc. Nationally Recognized Testing Laboratories (NRTLs – such as UL, CSA, Intertek, MET Labs, etc.) provide a valuable service to specifiers and end-users by testing the performance of all SPDs the same way. This is the only ‘common’ testing format in the industry, making it an important barometer of performance. Retrieved from Nemasurge 11-14-2013
UL 1703: Flat-Plate Photovoltaic Modules and Panels
1.1 These requirements cover flat-plate photovoltaic modules and panels intended for installation on or integral with buildings, or to be freestanding (that is, not attached to buildings), in accordance with the National Electrical Code, NFPA 70, and Model Building Codes. 1.2 These requirements cover modules and panels intended for use in systems with a maximum system voltage of 1000 V or less. 1.3 These requirements also cover components intended to provide electrical connection to and mounting facilities for flat-plate photovoltaic modules and panels. 1.4 These requirements do not cover: a) Equipment intended to accept the electrical output from the array, such as power conditioning units (inverters) and batteries; b) Any tracking mechanism; c) Cell assemblies intended to operate under concentrated sunlight; d) Optical concentrators; or e) Combination photovoltaic-thermal modules or panels.  
UL 1741: Inverter testing, Converters, Controllers and Interconnection System Equipment for Use With
UL1741 is an inverter testing standard from the UL global safety science organization that aims to ensure power system performance and grid support functionality.  1.1 The UL1741 inverter testing requirements cover inverters, converters, charge controllers, and interconnection system equipment (ISE) intended for use in stand-alone (not grid-connected) or utility-interactive (grid-connected) power systems. Utility-interactive inverters, converters, and ISE are intended to be operated in parallel with an electric power system (EPS) to supply power to common loads. 1.2 For utility-interactive equipment, the UL1741 inverter testing requirements are intended to supplement and be used in conjunction with the Standard for Interconnecting Distributed Resources With Electric Power Systems, IEEE 1547, and the Standard for Conformance Test Procedures for Equipment Interconnecting Distributed Resources with Electric Power Systems, IEEE 1547.1. 1.3 The UL1741 inverter testing requirements cover AC modules that combine flat-plate photovoltaic modules and inverters to provide AC output power for stand-alone use or utility interaction, and power systems that combine other alternative energy sources with inverters, converters, charge controllers, and interconnection system equipment (ISE), in system specific combinations. 1.4 The UL1741 inverter testing requirements also cover power systems that combine independent power sources with inverters, converters, charge controllers, and interconnection system equipment (ISE) in system-specific combinations. 1.5 The products covered by the UL1741 inverter testing requirements are intended to be installed in accordance with the National Electrical Code, NFPA 70. User-defined waveforms permit the generation of non-sinusoidal voltages: asymmetrical inflections, transient anomalies, voltage harmonics Equipment for Inverter Testing ​Grid Simulators are the most common equipment for UL1741