- Fixed SLC 500 controller with 12 24 V DC sinking inputs and 8 AC/DC relay outputs
- Input 0 provides the documented high-speed counter function
- DH-485 controller networking; RS-232 requires compatible interface equipment
1747-L20C is an Allen-Bradley fixed SLC 500 controller with integrated 20-point I/O and a dedicated high-speed counter input.
The controller combines 24 V DC sinking inputs, AC/DC relay outputs, user 24 V DC power, and a fixed SLC 500 processor in one unit.
Use the documented DH-485 arrangement for controller networking; RS-232 connections require a compatible interface module such as 1747-KE or 1770-KF3.
Availability, condition, price, and shipping time for 1747-L20C are confirmed during quotation.
Allen-Bradley 1747-L20C Fixed SLC 500 Controller Manuals, Product Family, Links
Important Notice: Other accessories, manuals, cables, calibration data, software, etc. are not included with this equipment unless listed in the above stock item description. All prices are shown in USD.
- Match field devices to the documented sinking-input arrangement
- Review relay contact load requirements before connecting loads
- Keep input and output commons consistent with the wiring diagram
- Use the high-speed input arrangement documented for the L20C
- Separate pulse wiring from high-noise conductors where required
- Confirm program scaling and counter operation before machine use
- DH-485 network support for the fixed SLC 500 controller
- RS-232 connectivity through compatible interface equipment such as 1747-KE or 1770-KF3
- Verify node, baud, cabling, and protocol settings after replacement
- Fixed SLC 500 machine control with integrated discrete I/O
- Pulse or count applications using input 0 high-speed counter
- DH-485-connected SLC 500 systems using compatible link equipment