UL-2231-2:2012 pdf free download – STANDARD FOR SAFETY Personnel Protection Systems for Electric Vehicle (EV) Supply Circuits: Particular Requirements for Protection Devices 21.2 The leakage current from any part to ground is permitted to exceed 0.5 MIU when components of the device are permitted to have leakage greater than 0.5 MIU. In no case shall the leakage current to ground exceed 3.5 MIU. See 21.12. The leakage current from one accessible part to another accessible part shall not exceed 0.5 MIU.
21.3 The leakage current of a device that incorporates a ground monitor/interrupter, when tested in accordance with 21.4— 21.10 and with the ground monitor/interrupter intentionally disabled, shall be no more than 5 MIU.
21.4 All accessible conductive surfaces shall be tested for leakage currents to determine compliance with
21.1. Where surfaces are simultaneously accessible, they shall be tested:
a) Individually,
b) Collectively (connected together) with the combined current measured to ground, and
c) Point-to-point on the device for leakage current between the simultaneously accessible surfaces.
Surfaces shall be regarded as simultaneously accessible when they are capable of being touched by one or both hands of a person at the same time. Accessible parts within a 100 mm by 200 mm (4 inch by 8 inch) rectangle are considered simultaneously accessible to one hand. The rectangle is able to be flexed or bent to closely conform to the surface of the device. Accessible parts that are capable of being touched at the same time by the ends of a string 1 .8 m (6 fl) in length are considered to be simultaneously accessible to both hands. The grounding pin, blade, or contact of an attachment plug is considered an accessible part.
21.5 When a surface other than metal is used for the enclosure or part of the enclosure, the leakage current shall be measured using metal foil with an area of 100 mm by 200 mm in contact with the surface. Where the surface is less than 100 mm by 200 mm, the metal foil shall be the same size as the surface. The metal foil shall not be pressed into openings and shall not remain in place long enough to affect the temperature of the representative device.
21.6 Typical measurement circuits for leakage current with the ground connection open are illustrated in Figures 2 and 3. The measurement instrument is defined in Figure 4. Over the frequency range of 20 Hz to 1 MHz with sinusoidal currents, the performance of the instrument shall be as follows:
a) The measured ratio Vi/Il with sinusoidal voltages shall be as close as feasible to the ratio Vi/Il calculated with the resistance and capacitance values of the measurement instrument
shown in Figure 4.
b) The measured ratio V3/ll with sinusoidal voltages shall be as close as feasible to the ratio V3/ll calculated with the resistance and capacitance values of the measurement instrument
shown in Figure 4. V3 shall be measured by the meter M in the measuring circuit. The reading of meter M in RMS volts is converted to MIU by dividing the reading by 500 ohms and then
multiplying the quotient by 1000. The mathematic equivalent is to multiply the RMS voltage
reading by 2.