1785-L26B

The Allen-Bradley 1785-L26B Enhanced PLC-5-26B is a programmable controller with protected memory, a 16-KB word processor, and a maximum I/O capacity of 512 I/O installed on the left-most slot of the 1771 I/O chassis, and it is used for controls and the management of the inputs and outputs of the field devices that are connected to it. It draws a maximum backplane current of 2.6 amps at 5 Volts DC from the 1771 I/O chassis power supply, and it offers voltage isolation between the communication ports that are tested at 500 Volts for 1 minute, and between the communication port and the relay cartridge that is tested at 1000 Volts for 1 minute. It can work with most 1771, 1794 I/O, 1746 I/O, and the 1791 8-point, 16-point, 32-point, and intelligent I/O modules. The 1785-L26B supports the (1785-RC) relay cartridge, which provides the interface with all external devices, and the controller itself can support up to 4 (0-3) I/O racks, and a maximum of 13 I/O chassis.

The 1785-L26B supports the 2-slot hardware addressing mode, with any mix of the 8-point modules, a pair of 16-point modules, and no 32-point module addressing, and the 1-slot addressing works with any mix of 8-point or 16-point modules, and a pair of 32-point modules. With the half-slot mode, the addressing can work for any mix of 8, 16, and 32-point modules. The controller can communicate through the 25-pin D-shell serial port, which supports the standard RS-232 and RS-423 serial interfaces, and it has a DH+ (Data Highway Plus) port for connection to the DH+ network, and it comes with a Remote I/O port (Channel 1B port) for Remote Connection. It has an ambient working temperature of around 0 to 60 degrees Celsius (32 to 140 degrees Fahrenheit) at an ambient humidity level of about 5-95% without condensation, and it is built to withstand an operational shock of 30G and a vibration of 1G at 10-500 Hertz. The 1785-L26B weighs approximately 1.42 kilograms (3 pounds) and comes in an open-style enclosure, and it is UL, CE, CSA, and C-TICK-certified.