Golden Dragon XML6125CLE, Руководство по ремонту

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德纳（北京）电机有限公司 Dana (Beijing) Electric Motor Co. Ltd
. 电话 Tel ： 010 － 69596333
北京市通州区宋庄 Songzhuang Tongzhou District Beijing 101118
德纳（北京）电机有限公司
Dana (Beijing) Electric Motor Co., Ltd.
7.4. Troubleshooting method for vehicle insulation faults
Note : When repairing and maintaining high-voltage components, shut down and wait for 3-5 minutes before
proceeding, and wait for the capacitors to discharge. 500V range shall be used to measure the insulation resistance of
MCU, and 1000V or above shall not be used for measurement.
When the vehicle's insulation reaches the highest insulation level, the vehicle is in the stop mode. If the vehicle can
still run normally after the key switch is restarted, the vehicle manufacturer is required to use an insulation resistance
meter to measure the insulation resistance of the high-voltage components separately. Unplug the electrical equipment
one by one from the high-voltage power distribution cabinet, and the vehicle manufacturer arranges personnel to get
along with the vehicle to test for that part of the insulation problem
When the vehicle's insulation reaches the highest insulation level, the vehicle is in the stop mode. If the vehicle cannot
run normally after the key switch is restarted, the vehicle manufacturer is required to use an insulation resistance
meter to measure the insulation resistance value of the high-voltage parts one by one. Supplier personnel arrived at
the site to troubleshoot.
Measure the MCU: Remove the DC bus from the MCU, use the insulation resistance meter to test the positive pole
to ground, and the negative pole to ground (insulation resistance meter test method: adjust the insulation resistance
meter to 500V voltage range, and the negative test lead to the MCU casing , The positive test lead touch the MCU's
bus terminal positive and negative) should be greater than 3M
Ω.
If it is less than 3M
Ω,
remove the phase cable and
test the insulation resistance of the MCU separately. If it is still less than 3M
Ω,
you need to replace the MCU. If it is
greater than 3M
Ω,
you need to test the motor and phase cable separately.
Measuring motor: The insulation resistance meter is adjusted to the voltage range of 1000V. The positive pole of the
test lead is to any one phase of each group, and the negative pole to the motor case the resistance value shall not be
less than 70M
Ω.
Measure phase cable: first visually check whether there is broken skin and whether the shielding layer is in contact
with the cable. If no problem is found above, adjust the insulation resistance meter to the voltage range of 1000V.
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