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1785-L20B

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1785-L20B
1785-L20B Wiring

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  • 1785-L20B
  • 1785-L20B Wiring
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The Allen-Bradley 1785-L20B is a PLC-5 Controller manufactured by Allen-Bradley. The 1785-L20B is one of the enhanced programmable controllers in the PLC-5 series. It is a programmable controller and it is the central part of every control system based in the Allen-Bradley PLC-5 series. The 1785-L20B Controller brings together I/O modules such as extended, local, and remote devices on different types of communication interfaces into one articulate control system perfect for some process control challenges. The Allen-Bradley 1785-L20B PLC-5 Controller features an integral port designed for the communication interface of the Data Highway Plus (DH+) network. The controller also has another port that is configurable into either DH+ or Remote I/O (scanner or adapter) networks. The DH+ communication network is suitable for the remote programming and monitoring of the 1785-L20B Controller, and it is used to create peer-to-peer communication networks between different controllers in the PLC-5 series.

The 1785-L20B features Remote I/O connection which is used for the real-time exchange of data between the I/O operator interface, the controller, and other devices. The front panel of this controller has a 25-pin connector marked channel 0 – EIA RS232C port and it is optically isolated. Channel 0 supports both the ASCII and the DF1 full-duplex and half-duplex slave protocols and the half-duplex master protocol. There is a Channel 0 communication indicator light that is always green on the front panel. Other than Channel 0, there is 8-pin mini-DIN connector marked as Channel 1A. There are also two 3-pin connectors as communication ports. Channel 1A and these ports are suitable for DH+ network communication. Port Channel 1B can be configured to work as a remote I/O scanner, a remote I/O adapter or as a DH+ communication port.

Other Automation PLC-5

SKU 2171437  UPC 0799705796522

AB PLC-5/20 Cntrlr. 16K Word SRAM 1785L 1785L2 1785L20

Troubleshooting and Product Information for 1785-L20B

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Other Automation
PLC-5 1785-L20B
Weight: 2 Lbs
Dimensions: 10"x12"x2"In
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1785-L20B
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Weight: 2 Lbs
Dimensions: 10"x12"x2"In
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Other 1785-L20B

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1785-L20B , CIM1785-L20B

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