The Allen-Bradley 1747-L40C is a part of the fixed hardware controller series that runs on a supply voltage of 20.4 - 27.6V DC or 24V DC +/- 15 % and a 120-240V AC line power. The 1747-L40C is a fixed controller that consists of a processor with 1,024 (1K) instruction capacities, a power supply, and a fixed number of I/O within a single package. With a capacitor-backed RAM, the 1747-L40C offers optional battery back-up and memory backup options through EEPROM or UVPROM. It has a 1K instruction capacity of program memory. The 1747-L40C has a nominal input current of 20mA at 24V DC for input 0 and 8mA at 24V DC for all other inputs.

With an on-state voltage of 10-30V DC and a maximum off-state voltage of 4V DC maximum for input 0 (5V DC for all others), the 1747-L40C has a maximum turn-on time and turn-off time of 8 milliseconds. The power output current of the 1747-L40C controller is 200mA and its power output voltage is 20.4 - 27.6V DC or 24V DC +/-15.

Moreover, the 1747-L40C uses a maximum of #14 AWG wire size and caters I/O electrical-optical isolation of 1500V AC at 1 minute. Operating in an ambient temperature rating of 0-60 deg. Celsius, this PLC module must be stored at the temperature of -40-85 deg. Celsius. The 1747-L40C has a typical scan time of an 8 milliseconds/1K and a program scan hold-up time after the loss of power of 20-700 milliseconds. The 1747-L40C possesses an I/O configuration input of (24) 24V DC sink inputs and an I/O configuration output of (16) AC/DC relay outputs. The 1747-L40C works with a high-speed counter and 24V/200mA user power.



Typical application of this fixed style controller is with small applications. However, this controller is capable of being integrated with Human Machine Interface (HMI), Supervisory Control and Data Acquisition (SCADA), programming device or 3rd party products. This may be achieved through direct interface to the embedded DH485 communication port or multiplexed with the use of 1747-AIC or 1761-NET AIC external couplers.

This PLC hardware is also capable of being extended by adding IO, specialty or intelligent module’s by adding a 1746-A2 or 2-Slot chassis. This allows a slightly expanded application, particularly if the embedded IO are not sufficient with the existing IO requirement.