PowerFlex 4-Class/520-Series Drives: RJ45 Connections / Terminating Resistors on RS485 Multi-Drive Connection Are Overheating

Summary

PowerFlex 4-Class/520-Series Drives: RJ45 connections / terminating resistors on RS485 multi-drive connection are overheating

Environment

• 22A PowerFlex 4
• 22B PowerFlex 40
• 22D PowerFlex 40P
• 22F PowerFlex 4M
• 23C PowerFlex 400
• 25A PowerFlex 523
• 25B PowerFlex 525

Answer

It is critical that the multi-drop connections are only made with the following components, as the other conductors within the RJ45 socket contain power.

• Splitter Cable: RJ45 one-to-two port splitter cable, Modbus only, AK-U0-RJ45-SC1
• Terminating Resistors: RJ45 120 Ω resistors, 2 pieces, AK-U0-RJ45-TR1
• Terminal Block: RJ45 two-position terminal block, 5 pieces, AK-U0-RJ45-TB2P

Important: Standard 8-pin RJ45 patch cables must not be used, as this may lead to drive malfunction and overheating of RJ45 connections / terminating resistors.

For further information, refer to QA18998 – PowerFlex 4-Class/520-Series Drives: RS485 Connection and Wiring.