The Allen-Bradley 1756-L61 is a ControlLogix controller. It has 2 MB user memory and 478 kb I/O memory available, with an optional non-volatile storage memory of 128 MB with the use of 1784-CF128 CompactFlash memory card. It is a chassis-based controller and can be placed in any available slot of the 1756 ControlLogix chassis. Compatible chassis for this controller are 1756-A4, 1756-A7, 1756-A10, 1756-A13, and the 1756-A17. It has an open-style type of enclosure and can support up to a maximum of 250 controller connections. It also has a built-in RS-232 serial communication port. Supported protocols of the RS232 port are DF1 full/half-duplex, ASCII, DF1 radio modem, Modbus via logic, and DH-485.
ManufacturerRockwell Automation
BrandAllen-Bradley
Part Number/Catalog No.1756-L61
SeriesControlLogix
Module TypeProcessor Module
Fixed Memory2, 4, or 8 MB
Nonvolatile MemoryCompact Flash Card 1784-CF128
Maximum I-O128,000
CommunicationRS-232 serial port
RS232 ProtocolsASCII DF1 full/half-duplex DF1 radio modem DH-485 Modbus via logic
Maximum Analog I-O4,000
Program Scan Time0.08 milliseconds
User Memory2MB
Backplane Current (5Volts DC)1.2 Amps
Backplane Current (24 Volts DC)14 milliamps
Weight0.71 pounds (0.32 kilograms)
Vibration10-500 Hertz
UPC10612598300706
Relative Humidity5-95 percent
Battery1756-BA1, 1756-BATM or 1756-BATA
UNSPSC32151705
Product Lifecycle Status*Discontinued/Obsolete
Full SupportProgramming Languages
It has a maximum digital I/O of 128,000, a maximum analog I/O of 4,000, and a maximum total I/O of 128,000. Controller tasks of the 1756-L61 include 32 tasks, 100 programs per task, and event tasks: all event triggers. The 1756-L61 has various communication options, such as ControlNet, Data Highway Plus, EtherNet/IP, DeviceNet, SynchLink, Remote I/O, and third-party process and device networks. The current draw of the 1756-L61 controller is 1200 mA at 5.1V DC and 14 mA at 24V DC. Power dissipation is at 3.5 W and thermal dissipation is 11.9 BTU/hr. It also has a continuous isolation voltage of 30V and has been tested at 720V DC for 60 s. It has an operating temperature of 0 to 60 Degrees Celsius, a storage temperature of -40 to 85 Degrees Celsius, and a maximum surrounding air temperature of 60 Degrees Celsius. Relative humidity is between 5% to 95% (noncondensing) and its vibration is 2 g at 10 to 500 Hz, with operating and non-operating shocks of 30 g and 50 g respectively.
1756-L61
Allen Bradley ControlLogix Processor Module with 2, 4, or 8 MB Fixed Memory
1756-L61S
GuardLogix Controller, 478 KB I-O Memory, 128000 Maximum I-O, 3.5 Watts