Posted 24 Mar 2022 Well, i'm working with a powerflex700S and it has a long time with us, we solve the faults that it had in that moment, but nowadays when we start the drive it shows RPM at the display, but the voltage output stays at 0. We tried with and without load and still the same problem, the display doesn't shows any alarm or fault, it just doesn't move the motor. We're trying to replicate the same conditions at the factory, but it just doesn't work. I suppose the motor is to small for the drive cause it works originally with an 800hp motor and we are working with an 50hp motor, but the employer wants to see the drive working before make any test at factory, Any idea you can give me to solve this problem... Thanks in advance Share this post Link to post Share on other sites
Posted 25 Mar 2022 Several things come to mind, starting with the huge mismatch between the motor and drive HP. This could be the biggest part of your problem. The drive is sensitive to that, as well as whether the motor is inductive of permanent magnet. When a PowerFlex drive is in V/Hz or SV (Volts-per-Hertz or Sensorless Vector) modes, the RPM displayed when running is essentially an estimate of speed based on the drive's output. However, you said that you're not getting any voltage output at R,S & T, correct? I've seen this on 755 drives in FV (FluxVector) mode when the encoder is wired incorrectly. The drive is trying to accelerate the motor but the encoder pulses are the wrong polarity. Is the motor using an encoder (other device) for speed feedback? If you have Connected Components Workbench, can you post a copy of the drive file here? There are just too many scenarios to go through and a look at the configuration would be a big help. Share this post Link to post Share on other sites
Posted 1 Apr 2022 Are you closed loop or open loop? Share this post Link to post Share on other sites
