Isolation resistance Clause Samples

Isolation resistance. This paragraph shall not apply to electrical circuits that are galvanically connected to each other, where the DC part of these circuits is connected to the electrical chassis and the specific voltage condition is fulfilled."

Isolation resistance. This paragraph shall not apply to electrical circuits that are galvanically connected to each other, where the DC part of these circuits is connected to the electrical chassis and the specific voltage condition is fulfilled. 5.1.3.1. Electric power train consisting of separate Direct Current- or Alternating Current-buses If AC high voltage buses and DC high voltage buses are galvanically isolated from each other, isolation resistance between the high voltage bus and the electrical chassis shall have a minimum value of 100 Ω/volt of the working voltage for DC buses, and a minimum value of 500 Ω/volt of the working voltage for AC buses. The measurement shall be conducted according to Annex 5A "Isolation resistance measurement method for vehicle based tests". 5.1.3.2. Electric power train consisting of combined DC- and AC-buses If AC high voltage buses and DC high voltage buses are galvanically connected, isolation resistance between the high voltage bus and the electrical chassis shall have a minimum value of 500 Ω/volt of the working voltage. However, if all AC high voltage buses are protected by one of the two following measures, isolation resistance between the high voltage bus and the electrical chassis shall have a minimum value of 100 Ω/V of the working voltage: (a) At least two or more layers of solid insulators, electrical protection barriers or enclosures that meet the requirement in paragraph 5. 1.1. independently, for example wiring harness; (b) Mechanically robust protections that have sufficient durability over vehicle service life such as motor housings, electronic converter cases or connectors; The isolation resistance between the high voltage bus and the electrical chassis may be demonstrated by calculation, measurement or a combination of both. The measurement shall be conducted according to Annex 5A "Isolation resistance measurement method for vehicle based tests". 5.1.3.3. Fuel cell vehicles In fuel cell vehicles, DC high voltage buses shall have an on-board isolation resistance monitoring system together with a warning to the driver if the isolation resistance drops below the minimum required value of 100 Ω/V. The function of the on-board isolation resistance monitoring system shall be confirmed as described in Annex 6. The isolation resistance between the high voltage bus of the coupling system for charging the REESS, which is not energized in conditions other than that during the charging of the REESS, and the electrical chassis need no...

Isolation resistance. If the electrical circuit divided by the disconnect function includes AC circuit, this part of the high voltage bus shall be considered as an AC high voltage bus. If the electrical circuit divided by the disconnect function doesn't include AC circuit, this part of the high voltage bus shall be considered as a DC high voltage bus. For AC high voltage buses, isolation resistance between the high voltage bus and the electrical chassis shall have minimum value of 500 ohms/volt of working voltage. If the protection degree IPXXB is satisfied for AC portion of the high voltage buses after crash, isolation resistance between the high voltage bus and the electrical chassis shall have minimum value of 100 ohms/volt of working voltage. For DC high voltage buses, isolation resistance between any high voltage bus and the electrical chassis shall have minimum value of 100 ohms/volt of working voltage.

Isolation resistance. 5.5.1.4.1 Electric power train consisting of separate DC- or AC-buses If AC high voltage buses and DC high voltage buses are galvanically isolated from each other, isolation resistance 5.5.1.4.2 Electric power train consisting of combined DC- and AC-buses If AC high voltage buses and DC high voltage buses are galvanically connected isolation resistance between the high

Isolation resistance. This paragraph shall not apply to chassis connected electrical circuits where the maximum voltage between any live part and the electrical chassis or any exposed conductive part does not exceed 30 V AC (rms) or 60 V DC. 5.1.3.1. Electric power train consisting of separate Direct Current- or Alternating Current-buses Public Comment If AC buses and DC buses are galvanically isolated from each other, the isolation resistance between the high voltage bus and the electrical chassis shall have a minimum value of 100 Ω/V of the working voltage for DC buses, and a minimum value of 500 Ω/V of the working voltage for AC buses. The measurement shall be conducted according to Annex 4A "Isolation resistance measurement method for vehicle based tests". 5.1.3.2. Electric power train consisting of combined DC- and AC-buses If AC buses and DC buses are galvanically connected, isolation resistance between any high voltage bus and the electrical chassis shall have a minimum value of 500 Ω/volt of the working voltage. However, if all AC high voltage buses are protected by one of the two following measures, isolation resistance between any high voltage bus and the electrical chassis shall have a minimum value of 100 Ω/V of the working voltage:

Isolation resistance. The isolation resistance between the high voltage bus and the electrical chassis may be demonstrated either by measurement or by a combination of measurement and calculation. The following instructions should be used if the isolation resistance is demonstrated by measurement. Measure and record the voltage (Vb) between the negative and the positive side of the high voltage bus (see figure 1); Measure and record the voltage (V1) between the negative side of the high voltage bus and the electrical chassis (see figure 1); Measure and record the voltage (V2) between the positive side of the high voltage bus and the electrical chassis (see figure 1); If V1 is greater than or equal to V2, insert a standard known resistance (Ro) between the negative side of the high voltage bus and the electrical chassis. With Ro installed, measure the voltage (V1’) between the negative side of the high voltage bus and the vehicle electrical chassis (see figure 3). Calculate the isolation resistance (Ri) according to the formula shown below. Ri = Ro*(Vb/V1’ – Vb/V1) or Ri = Ro*Vb*(1/V1’ – 1/V1) Divide the result Ri, which is the electrical isolation resistance value in ohm (Ω), by the working voltage of the high voltage bus in volt (V). Ri (Ω / V) = Ri (Ω) / Working voltage (V) Figure 3 Measurement of V1' If V2 is greater than V1, insert a standard known resistance (Ro) between the positive side of the high voltage bus and the electrical chassis. With Ro installed, measure the voltage (V2’) between the positive side of the high voltage bus and the electrical chassis (see figure 4). Calculate the isolation resistance (Ri) according to the formula shown below. Ri = Ro*(Vb/V2’ – Vb/V2) or Ri = Ro*Vb*(1/V2’ – 1/V2) Divide the result Ri, which is the electrical isolation resistance value in ohm (Ω), by the working voltage of the high voltage bus in volt (V). Ri (Ω / V) = Ri (Ω) / Working voltage (V) Figure 4 Measurement of V2' Note 1: The standard known resistance Ro (in Ω) should be the value of the minimum required isolation resistance (Ω/V) multiplied by the working voltage (V) of the vehicle plus/minus 20 per cent. Ro is not required to be precisely this value since the equations are valid for any Ro; however, a Ro value in this range should provide a good resolution for the voltage measurements.