Document ID: chunk:federal_register_of_legislation:F2023L01529:body:0:p28
Version: federal_register_of_legislation:F2023L01529
Segment Type: other
Provision Reference: 
Character Range: 78302–81380

Table 1
Access probes for the tests for protection of persons against access to hazardous parts

Figure 1
Jointed Test Finger

       Material: metal, except where otherwise specified

Linear dimensions in millimeters

Tolerances on dimensions without specific tolerance:

       (a) On angles: 0/-10 seconds;

       (b) On linear dimensions:

            (i) up to 25 mm: 0/-0.05 mm:
            (ii) over 25 mm: ±0.2 mm.

Both joints shall permit movement in the same plane and the same direction through an angle of 90° with a 0 to +10° tolerance.

Annex 4A

Isolation resistance measurement method for vehicle based tests

       1. General

        The isolation resistance for each high voltage bus of the vehicle shall be measured or shall be determined by calculation using measurement values from each part or component unit of a high voltage bus (hereinafter referred to as the "divided measurement").

       2.  Measurement method

        The isolation resistance measurement shall be conducted by selecting an appropriate measurement method from among those listed in paragraphs 2.1. through 2.2. of this annex, depending on the electrical charge of the live parts or the isolation resistance, etc.

        The range of the electrical circuit to be measured shall be clarified in advance, using electrical circuit diagrams, etc.

        Moreover, modification necessary for measuring the isolation resistance may be carried out, such as removal of the cover in order to reach the live parts, drawing of measurement lines, change in software, etc.

        In cases where the measured values are not stable due to the operation of the on-board isolation resistance monitoring system, etc., necessary modification for conducting the measurement may be carried out, such as stopping of the operation of the device concerned or removing it. Furthermore, when the device is removed, it shall be proven, using drawings, etc., that it will not change the isolation resistance between the live parts and the electrical chassis.

        Utmost care shall be exercised as to short circuit, electric shock, etc., for this confirmation might require direct operations of the high-voltage circuit.

       2.1.  Measurement method using voltage from off-vehicle sources

       2.1.1. Measurement instrument

        An isolation resistance test instrument capable of applying a DC voltage higher than the working voltage of the high voltage bus shall be used.

       2.1.2. Measurement method

        An insulator resistance test instrument shall be connected between the live parts and the electrical chassis. Then, the isolation resistance shall be measured by applying a DC voltage at least half of the working voltage of the high voltage bus.

        If the system has several voltage ranges (e.g. because of boost converter) in galvanically connected circuit and some of the components cannot withstand the working voltage of the entire circuit, the isolation resistance between those components and the electrical chassis can be measured separately by applying