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F07900 (N, A) Drive: Motor blocked V4.5

Created by: GregMan-SCA at: 11/13/2013 7:35 PM (5 Replies)

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11/13/2013 7:35 PM	Rate (0)
GregMan-SCA Member Joined: 11/4/2013 Last visit: 8/5/2025 Posts: 5 Rating: (0)	I made a VSDtraining model: 0.12kW 400VAC 50Hz motor Y connected+0.75kW PM240 power unit + CU240E-2. My line supply is 1ph 400VAC 60Hz connected toL & N terminals. Commissioning: 1. Using IOP wizard: in the end of the wizard during SAVE SETTING step I got amessage "Saving of settings failed"; 2. Using Starter:Wizard Commissioning done with Restored Factory settings. I try to run the motor using Control Panel: -ZERO speed setting - VSD fan running, NO Warnings and NO Alarms. - NON ZERO speed setting - motor shaft dosn't move and I got the Fault "F07900 (N, A) Drive: Motor blocked V4.5" Remedy dosn't help. Motor tested for Insulation (Found Good), Winding resistance (symmetrical), Shaft turning well, DOL start and run without problem. PM240 Power Unit tested using Fluke 87III: Rectifier and Converter Diods GOOD, + & - DC polesresistance 3.3MOhm. Please your advise on the source of the fault. Thanks

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11/14/2013 9:08 PM	Rate (0)
zako_ Gold Member Joined: 5/22/2012 Last visit: 3/24/2022 Posts: 895 Rating: (67)	first I would test the V/f mode - this has to work!

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11/14/2013 9:12 PM	Rate (0)
GregMan-SCA Member Joined: 11/4/2013 Last visit: 8/5/2025 Posts: 5 Rating: (0)	I tested all modes with open loop, and encorderless. Same fault.

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11/14/2013 9:42 PM	Rate (0)
zako_ Gold Member Joined: 5/22/2012 Last visit: 3/24/2022 Posts: 895 Rating: (67)	... you can disconnect the motor und switch on in V/f mode - the motor should not go in fault. So you would know that isn`t a powermodule problem.

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11/14/2013 10:11 PM	Rate (0)
GregMan-SCA Member Joined: 11/4/2013 Last visit: 8/5/2025 Posts: 5 Rating: (0)	Do you mean disconnect the motor from VSD and run the VSD without motor on V/f mode, idn't it?

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11/15/2013 1:21 PM	Rate (0)
Technology Team Platinum Expert Joined: 10/11/2006 Last visit: 8/29/2025 Posts: 6037 Rating: (828)	Hello V/f - mode will work without a conntected motor too. So you can check, if your powermodule has a problem or not.
	With best regards, Technology Team Application consulting and pre sales support for SINAMICS, SIMATIC Technology, SIMOTION, SIMOTICS and MOTION CONNECT
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