GE Industrial Solutions AF-600 FP High Power Unit Sizes 6x - Manual (Page 79)

6.2.2.2 Inverter test part I
1. Connect the positive (+) meter lead to the (+) positive DC bus bar.
2. Connect the negative (–) meter lead to terminals U, V, and W in sequence.
2
3
1
4
5
1 Top (-)DC link fuse bus bar 4 (+)DC link fuse
2 (-)DC link fuse 5 Bottom (+)DC link fuse bus bar
3 Top (+)DC link fuse bus bar
Each reading should show infinity. The meter will start at a low value and slowly climb toward infinity due to capacitance within the frequency converter being
charged by the meter.
Inverter test part II
1. Reverse the meter leads by connecting the negative (–) meter lead to the positive (+) DC bus bar.
2. Connect the positive (+) meter lead to U, V, and W in sequence. Each reading should show a diode drop.
Incorrect reading
An incorrect reading in any inverter test indicates a failed IGBT in that inverter module. Replace the IGBT module according to the disassembly instructions. The
inverter module must be removed to replace the IGBT module.
Inverter test part III
1. Connect the positive (+) meter lead to the negative (-) DC bus bar.
2. Connect the negative (–) meter lead to terminals U, V, and W in sequence. Each reading should show a diode drop.
Inverter test part IV
1. Reverse the meter leads by connecting the negative (–) meter lead to the negative (-) DC bus bar.
2. Connect the positive (+) meter lead to U, V, and W in sequence.
Each reading should show infinity. The meter will start at a low value and slowly climb toward infinity due to capacitance within the frequency converter being
charged by the meter.
Incorrect reading
An incorrect reading in any inverter test indicates a failed module. Replace the IGBT module according to the disassembly instructions. The inverter module must
be removed to replace the IGBT module.
High Power Service Manual for Unit Sizes 6x
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