Allen-Bradley 1756-L71 ControlLogix Programmable Automation Controller

The Allen-Bradley 1756-L71 is a ControlLogix Programmable Automation Controller. It has an available storage of 2 MB for user memory and an I/O memory of 0.98 MB. It also has an onboard 4-character alphanumeric display for easy monitoring of run-time and module information and controller diagnostics. It has an open-style enclosure and built-in One (1) 2.0 full-speed USB port available. The communication options that are available include DeviceNet, ControlNet, EtherNet/IP, Remote I/O Data Highway Plus, Third-party process and networks, and SynchLink. It also ships with a 1 GB non-volatile memory, but you can upgrade it to 2 GB with the 1784-SD2. It is recommended that the SD card be left installed in the controller. The 1756-L71 controller ships with three capacitor energy storage modules, two of which are removable. It has a current draw of 5 mA at 1.2 Volts DC and 800 mA at 5.1 Volts DC. 

Technical specifications for 1756-L71

ManufacturerRockwell Automation

Maximum Analog I-O4000

Maximum I-O128000

Part Number/Catalog No.1756-L71

Module TypeProcessor Module

SeriesControlLogix

BrandAllen-Bradley

Product TypeProgrammable Automation Controller

Non-volatile memory1GB (ships with the controlelr)

No. of task32

Programs per task100 Programs

Event TaskAll Triggers

Built-in communication1 USB port

Optional Communication adapters? EtherNet/IP ? ControlNet ? DeviceNet ? Data Highway Plus ? Remote I/O ? SynchLink ? Third-party process and device networks

RedundancyFull Support

Integrated Motion? SERCOS interface Analog options (encoder input, LDT input, SSI input) ? Integrated Motion on the EtherNet/IP network

I-O Memory0.98 MB

User Memory2 MB

Maximum Digital I-O128,000

Current Draw (1.2 Volts DC)5 milliamps

Current Draw (5.1 Volts)800 milliamps

Power Dissipation2.5 Watts

Thermal Dissipation8.5 BTU per hour

Isolation Voltage30 Volts Continuous

EnclosureNone

CommunicationDeviceNet, ControlNet, EtherNet/IP, Remote I/O

The 1756-L71 controller also has a continuous isolation voltage of 30 Volts, a maximum power dissipation of 2.5 Watts, and a thermal dissipation of 8.5 BTU/hour. It has a maximum analog I/O, digital I/O, and a total I/O of 4,000, 128,000, as well as 128,000, respectively. It has an operating temperature range of 0 to 60 Degrees Celsius and a storage temperature range of -40 to 85 Degrees Celsius. Its maximum surrounding air temperature is 60 degrees Celsius and it has a noncondensing relative humidity of 5% to 95%. The controller has a vibration of 2G at 10 to 500 Hertz, an operating shock of 30G, and a non-operating shock of 50G that goes down to 45G when the SD card is installed. Other controllers may require the user to understand first PLC registers specifically Byte and Bit in order to start addressing program elements. With 1756-L71, the user simply needs to insert a program element and select the logical channel to where the I/O is physically wired. In other PLCs, the user may find the need to move a register to another to initiate conversion and processing just to get the analog data. This controller simply requires the user to find the logical channel where the I/O signal is physically terminated.

1756-L71K

Allen Bradley ControlLogix Processor Module with 0.98 MB I-O Memory

1756-L71S

GuardLogix Controller, 0.98 MB I-O Memory, 128000 Maximum I-O, 2.5 Watts

1756-L71SK

GuardLogix Controller, 0.98 MB I-O Memory, 128000 Maximum I-O, 2.5 Watts, Conformal Coat