support.automation.siemens.com | Technical Forum | Friday, March 14, 2025 4:44:41 AM
SINAMICS BRAKING MODULE INPUT: 1035 V DC OUTPUT: 250 KW/15 S problem
Created by: Deep Bhatt at: 5/17/2011 10:09 AM (9 Replies)
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| 5/17/2011 10:09 AM | |
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Posts: 241 Rating:
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In my case I have connected DBU to g130.. Problem is dbu is always giving DC voltage at o/p whether its in regenration(D.C link overvoltage) or not. I have On/Off the inhibit signal of DBU but it doesnt make any diffrence. also DBU healthy bit is whether On/Off DBU giving voltage.. I am atteching my testing points here.. |
| 5/26/2011 7:03 PM | |
Joined: 9/20/2006 Last visit: 3/5/2024 Posts: 307 Rating:
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you have to check the voltage across the braking resistor when only the supply is no. no on commant ig given to the drive. if you find voltage across the braking resistorterminals surely either the connections of the braking unit are incorrect or the braking unit is def. |
| 5/29/2011 8:24 AM | |
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Posts: 241 Rating:
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ya i have checked what u said..because of this i faced power module-precharging ckt burn out problem so i have removed connection of DBR for safety perpous.. but problem is there when i set the inhibit for DBU off .and whether i give on/off to DBU healthy bit it still giving me DC voltage. and without giving on command there is no voltage accross dbu.. |
Last edited by: Deep Bhatt at: 5/29/2011 8:26 AM |
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| 5/30/2011 6:33 AM | |
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Joined: 9/20/2006 Last visit: 3/5/2024 Posts: 307 Rating:
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when u say voltage across dbu, can u tell me where have you checked the dc voltage.? i mean which terminals? diwa. |
| 5/31/2011 4:19 AM | |
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Posts: 241 Rating:
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At output terminal of dbu |
| 5/31/2011 5:12 AM | |
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Joined: 9/20/2006 Last visit: 3/5/2024 Posts: 307 Rating:
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Dear Deep, A braking unit (DBU) does not have an o/p. it has only the dc terminals positive and negative AND the terminals for the braking resistor (DBR). If you are measuring the voltage across the DBR terminals and you can see voltage there even when the DC voltage is below the switching level of the DBU there is problem. 1) the DBU is def. OR 2) the DC positive and the DC negative terminals are not connected correctly( reversed). Diwa. |
| 6/1/2011 10:50 AM | |
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Posts: 241 Rating:
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i have checked the DC voltage at DBR terminal... And i have also atteched the testing points here |
| 6/1/2011 10:52 AM | |
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Posts: 241 Rating:
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and if the DC positive and the DC negative terminals are not connected correctly( reversed). the converter inside DBU should be damaged but its giving me proper reading...as mentionedin attached file |
| 6/1/2011 1:09 PM | |
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Joined: 9/20/2006 Last visit: 3/5/2024 Posts: 307 Rating:
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it looks like the problem is with your DBU. have you replaced the dbu and checked? |
| 6/2/2011 8:07 AM | |
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Posts: 241 Rating:
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I have ordered new DBU..but same problem is coming in all 5 drive units... |