Rockwell Automation 7000L PowerFlex Medium Voltage AC Drive (C Frame) - Classic Control User Manual
Page 278
Commissioning 4-73
7000 “C” Frame
7000L-UM300I-EN-P – Juen 2013
Input Phasing Check
There are 9 voltage test points on the Line Signal Conditioning
Board that will allow you to look at each voltage connection
individually.
These test points are labeled as follows:
Table 4.C – SCBL Test Points and Associated Voltage Signals
Test Point
Description
Isolation Transformer:
Secondary Phasing and Bridge
Phase Relationship with
respect to Vab1-Out (2U)
Vab1-Out
2U
Master
–
Vbc1-Out
2V
Master
-120°
Vca1-Out
2W
Master
-240°
Vab2-Out
3U
Slave 1
-20°
Vbc2-Out
3V
Slave 1
-140°
Vca2-Out
3W
Slave 1
-260°
Vab3-Out
4U
Slave 2
+20°
Vbc3-Out
4V
Slave 2
-100°
Vca3-Out
4W
Slave 2
-220°
All of these test points can be measured to either the Analog Ground
on the board or the TE ground in the low voltage section. You can
use Vab1-Out as your reference (trigger on this waveform) and
verify all the other test points using the table above. It is easier to
use zero crossings on your oscilloscope as the reference points when
checking the phase shifts.
Essentially, you are verifying the following relationships:
1. V and W in each bridge should be lagging U by 120° and 240°,
respectively.
2. 3U, 3V, and 3W should be lagging 2U, 2V, and 2W by 20°
(-20°), respectively.
3. 4U, 4V, and 4W should be leading 2U, 2V, and 2W by 20°
(+20°), respectively.