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1785-LT4

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1785-LT4
1785-LT4 Wiring

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  • 1785-LT4
  • 1785-LT4 Wiring
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The 1785-LT4 PLC-5 processor belongs to the 1785 Classic series of Allen-Bradley’s Programmable Controller modules. The module is designed to operate with PLC-5 platforms that require a 120-Volt supply. The 1785-LT4 requires a circuit board that offers 2.5 Amps at 5 Volts DC. The 1785-LT4 PLC-5 processor has a maximum analog input/output of 512. The I/O module offers a maximum scan time of 2 milliseconds for discrete logic programs and 8 milliseconds for typical programs. In order to maximize the scan time, the input/output rack must be divided between multiple channels. The Allen-Bradley 1785-LT4 is an Industrial Equipment Class 1 processor that operates in different conditions and environments. However, appropriate precautions are required under hot and high-radiation environments, because its electromagnetic compatibility may be affected. The PLC-5 processor can operate under 60 degrees Celsius, and can withstand up to 85 degrees Celsius.

The 1785-LT4 is a PLC-5/10 processor that features a communication indicator at the top, a key-switch, a programming terminal port, a DH+ port, and a remote I/O port. A 9-pin, D-shell programming terminal is required to connect to the processor parallel with the 3-pin DH+ communication link connector and a 2-pin remote I/O link connector. All I/O channels scan independently, which means that the remote I/O scanning on one channel will not affect the I/O scanning on other channels. The remote transmission rate of the module is 57.6 kilobytes per second. Moreover, it has a memory of 6K words. While installing the PLC-5 processor, disconnect the power supplies from the chassis as well as the power arm. It is advisable not to touch the pins, and the workstation must be static-free. Also, the relative humidity should be between 40% and 60%. For the installation of the 1785-LT4 processor, the first step is to locate the switch assembly – SW1 in the system, and set the switches according to the user manual. Configure the Adapter Mode communication by defining the I/O rack number and the I/O group of the processor in the adapter mode. Locate the SW2 switch assembly and set it according to the use of the processor in the adapter mode. Locate and set the SW3 switch assembly according to the manual and then install the keying bands in the backplane sockets. Insert the first keying band between the pins numbered 40 and 42, and the second one should be inserted between 54 and 56. Then, insert the processor into the I/O chassis and secure it with the module-locking latch.

Other Automation PLC-5

SKU 2171453  UPC 0799705803138

Module Processor Memory

Troubleshooting and Product Information for 1785-LT4

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Other Automation
PLC-5 1785-LT4
Weight: 2 Lbs
Dimensions: 10"x12"x2"In
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1785-LT4
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Weight: 2 Lbs
Dimensions: 10"x12"x2"In
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