Product Summary
The 1785-L20C15 ControlNet PLC-5 processor merges local and remote I/O into one coherent system. It handles 512 forcible I/O points with 16-kiloword user memory. This controller uses a lithium battery for backup and dissipates only 54 BTU per hour. Engineers rely on its 0.5ms average scan time for deterministic control.
Why Procurement Managers Choose the 1785-L20C15
This ControlNet processor delivers 77 total I/O chassis capacity, 12 of which support universal remote I/O. It supports both scheduled and unscheduled peer-to-peer communication on ControlNet. The 1785-L20C15 integrates seamlessly with existing PLC-5 systems. Its backplane current load is 2.7 A at 5 V typical. This low current draw reduces power supply sizing costs. The module uses a standard lithium battery for program backup. You can also install an EEPROM module for additional security.
Forcible total I/O reaches 512 points in any mix. Complementary mode offers 384 inputs and 384 outputs. Non-forcible I/O scales to 3,200 points. Analog I/O reaches 512 forcible and 32,000 non-forcible. These figures simplify scaling for growing production lines. The processor also supports up to 12 universal remote I/O chassis. This flexibility reduces wiring and installation costs.
Expert Technical Evaluation of the 1785-L20C15
The 1785-L20C15 integrates a ControlNet phase 1.5 interface. It cannot mix with phase 1.0 or 1.25 devices. Scan time per ControlNet rack averages 0.5 ms. Universal remote I/O scan time ranges from 3 ms to 10 ms depending on baud rate. This ensures real-time I/O updates for fast processes. The processor includes one RS-232-C/422-A/423-A port. It supports ASCII and DF1 protocols. Channel 1A is dedicated to Data Highway Plus. Channel 1B can be configured as remote I/O scanner or adapter.
Memory consists of 16 kilowords of battery-backed static RAM. Protected memory is not available. The processor uses a three-position keyswitch for RUN, PROG, and REM modes. Front-panel LEDs indicate battery, processor, force, and communication status. Heat dissipation is only 54 BTU per hour. This allows installation in tight enclosures without extra cooling.
Logistics & Standard Packaging Details
Express delivery is available via FedEx, UPS, and DHL.
