adccommunitymod (AutomationDirect) asked a question.
Created Date: August 22,2012
Created By: mwdkmpr
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I have 5 GS drives on a RS485 network from port 2 of a DL260 PLC. Cable runs about 4 ' from port 2 to a ZL-COM-RJ12X4. There are two drives within 4 ' of this jack. Then there is a 12 ' cable from there to another ZL-COM-RJ12X4 with two drives within 4 ' and another within 12 '. There is one 25HP drive that when it is running will cause the com to fail. I took P2.08 down to 3 and it will run longer but it will still fail. This drive is within 4 ' of he second ZL-COM-RJ12X4. I want to do a pure daisy chain instead of the star/daisy chain combo. But I can't because of the single RJ12 jack on the drives. Any ideas?
Created Date: August 23,2012
Created by: Bob S BN
I want to do a pure daisy chain instead of the star/daisy chain combo. But I can't because of the single RJ12 jack on the drives.
Perhaps this guy will allow you to get each drive port broken out into terminal blocks for the daisychain.:confused:
http://www.automationdirect.com/adc/Shopping/Catalog/Wiring_Solutions/ZipLink_Pre-Wired_Connection_Cables_-a-_Modules/ZipLink_Specialty_Modules_-a-_Cables/ZL-RTB-RJ12
Created Date: August 23,2012
Created by: bcarlton
Justy a note, AB providess for its drives which have an RJ45 socket for its RS485 connections a RJ45 plug - to - 2 screw terminal aadapter which breaks out the two data lines (AK-U0-RJ45-TB2P). It makes it much easier to to a daisy chain. Perhaps if something similar were to be done for the GS dirves with their RJ12 sockets.
Created Date: August 23,2012
Created by: Do-more PE
I passed the suggestion along Bernie.
Created Date: August 23,2012
Created by: bcarlton
Good - they sell them in packages of 5 and add in a couple terminating resistors. Very handy and a reminder.
Created Date: August 23,2012
Created by: mwdkmpr
Justy a note, AB providess for its drives which have an RJ45 socket for its RS485 connections a RJ45 plug - to - 2 screw terminal aadapter which breaks out the two data lines (AK-U0-RJ45-TB2P). It makes it much easier to to a daisy chain. Perhaps if something similar were to be done for the GS dirves with their RJ12 sockets.
Will these (AK-U0-RJ45-TB2P) work with the GS drive? Do you think that a true daisy chain will fix this problem? Could it be something wrong with the drive? Com only fails when this drive is on.
Created Date: August 23,2012
Created by: bcarlton
The AB is for an RJ45 socket (which is on their Powerflex drives). The GS have an RJ11 socket. Also the terminals must be attache to the proper two pins.
I have no guess whether doing this as a pure daisy chain would solve the problem. It couldn't hurt though. Cable routing and proper termination (though you didn't mention termination) would be tyhe best bet.
Make sure the last drive is properly grounded. It may possibly need infeed reactors on the power line.
Created Date: August 24,2012
Created by: mwdkmpr
Cable routing and proper termination (though you didn't mention termination) would be tyhe best bet.
How do you put a termination resistor on a modular plug? I have ordered several of the ZL-RTB-RJ12 and am going to use them with a short pigtail to the drive.
Make sure the last drive is properly grounded. It may possibly need infeed reactors on the power line.
I will double check ground continuity. All drives have line and load reactors.
It only happens when this one drive is on. All of the others work fine until this drive starts. It is not the largest, smallest, furthest, nor is there any other thing unique about it. Other than it is the only 25HP drive. Could there be something wrong in the drive causing the problem?
Created Date: August 24,2012
Created by: Do-more PE
Is the motor grounded to the drive chassis or to some point in the control cabinet?
Created Date: August 24,2012
Created by: mwdkmpr
ADC App Assist Is the motor grounded to the drive chassis or to some point in the control cabinet?
To a ground buss in the cabinet.
Created Date: August 24,2012
Created by: Do-more PE
Unlike all other grounds, motors driven by a VFD need to be grounded directly to the VFD chassis. See pages 2-18 & 2-19 of the GS3 Drive Manual .