There are two important steps before the drive is powered on: the first step is to judge the quality of the IPM. The use of the second gear of the universal table, red pen -, black pen respectively r, S, T, U, V, W and other terminals, check the value of about 0.5 is good, black pen connection plus, red pen respectively connected R, S, T, U, V, W terminals, check the value of about 0.5 is good. If not 0.5, the IPM is corrupted.
After two measures of the value is about 0.5, can only show that the IPM within the continuous flow diode is good, at this time also need to iPM coupling of optocoupled detection: with the second gear, red pen 5 feet, black pen 6 feet, the value of about 0.55 is good, and then the red pen 7 feet, black pen 8 feet, the value of 0.77 or so is good, so that it can be illustrated light coupling and IPM work of the work of the Can be intact. Conversely, damage to IPM and optocoupler occurs.
The second step is to judge the switch power supply MOS good or bad: in the repair to see the gate pole resistance charred or measured a change in the gate extreme resistance value, indicating that the gate resistance and MOS and connected 2844 is broken. Power-up or no display or display after all replacements indicates that the voltage is too high, and the most likely cause of failure is the four-foot optocoupler damage of the PC9.
If after the first step and the second step of detection still found no point of failure, the drive or no display, it is likely that the switching power diode is broken. In the repair to judge the diode is good or bad methods as follows: red diode positive, black-socket, one model 0.4-0.5 is good, the other is 0.2-0.3 is good. If the switch ingress power supply is bad: the power fan does not turn, the voltage is low, the D3 diode is measured in reverse are 0.14-one diode bad.