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Allen-Bradley 1756-L73S is a Logix 5573S automation controller with 8 MB user memory and 4 MB safety memory, with standard and safety communication options on EtherNet/IP, ControlNet and DeviceNet.
- Manufacturer
- Allen-Bradley
- Manufacturer part no.
- 1756-L73S
- Product family
- ControlLogix and GuardLogix Controllers (1756)
- Type
- GuardLogix safety controller
- Lifecycle
- Active
- OEM successor
- Not stated
- Technical datasheet
- Data sheet
Technical specifications
- Manufacturer
- Allen-Bradley
- Manufacturer part no.
- 1756-L73S
- Type
- GuardLogix safety controller
- Application
- PLC controller
- Used with
- ControlLogix 1756 chassis
- Safety communication options
- Standard and safety, EtherNet/IP, ControlNet, DeviceNet
- Network connections per network module
- 1000 I/O; 528 EtherNet/IP; 512 TCP (1756-EN4TR) 256 EtherNet/IP; 128 TCP (1756-EN2x) 128 EtherNet/IP; 64 TCP (1756-ENBT) 128 ControlNet (1756-CN2/B) 100 ControlNet (1756-CN2/A) 40 ControlNet (1756-CNB/D, 1756-CNB/E)
- Programming languages
- For the safety task, GuardLogix controllers support Ladder Diagram only., For standard tasks, GuardLogix controllers support: – Ladder Diagram (LD) – Structured Text (ST) – Function Block Diagram (FBD) – Sequential Function Chart (SFC)
- User memory
- 8 MB
- Safety memory
- 4 MB
- I/O memory
- 0.98 MB
- Nonvolatile memory storage
- 1 GB Secure Digital (SD) card (1784-SD1), ships pre-installed in the controller
- Digital I/O, max
- 128,000
- Analog I/O, max
- 4000
- Total I/O, max
- 128,000
- Energy storage modules
- 1756-ESMCAP capacitor energy storage module (removable, ships installed with every controller) 1756-ESMNSE capacitor energy storage module (removable, no residual, WallClockTime power backup) 1756-ESMNRM capacitor energy storage module (non-removable, helps prevent USB connection and SD card use to help secure the controller)
- Current draw @ 1.2V DC
- 5 mA
- Current draw @ 5.1V DC
- 800 mA
- Power dissipation
- 2.5 W
- Thermal dissipation
- 8.5 BTU/hr
- Isolation voltage
- 30V (continuous), basic insulation, USB port-to-system, Compliant and tested according to IEC/UL 61010-1
- Weight, approx
- 0.25 kg (0.55 lb)
- Slot width
- 2 (both modules needed; each is one slot)
- Module location
- Chassis-based, any slot
- Chassis
- 1756-A4, 1756-A4K, 1756-A7, 1756-A7K, 1756-A10, 1756-A10K, 1756-A13, 1756-A13K, 1756-A17, 1756-A17K
- Power supply, standard
- 1756-PA50, 1756-PA50K, 1756-PA72, 1756-PA72K, 1756-PA75, 1756-PA75K, 1756-PB50, 1756-PB50K 1756-PB72, 1756-PB72K, 1756-PB75, 1756-PB75K, 1756-PC75, 1756-PH75
- Power supply, redundant
- 1756-PA75R, 1756-PA75RK, 1756-PB75R, 1756-PB75RK, 1756-PSCA2, 1756-PSCA2K
- Wire category
- 3 - on USB ports
- Temperature code
- T4
- Enclosure type rating
- None (open-style)
Show all 40 specificationsShow fewer
- Temperature, operating
- 0 °C ≤ Ta ≤ +60 °C (+32 °F ≤ Ta ≤ +140 °F)
- Temperature, nonoperating
- -40…+85 °C (-40…+185 °F)
- Relative humidity
- 5…95% noncondensing
- Vibration
- IEC 60068-2-6 (Test Fc, Operating)
- Shock, operating
- IEC 60068-2-27 (Test Ea, Unpackaged Shock)
- Shock, nonoperating
- IEC 60068-2-27 (Test Ea, Unpackaged Shock)
- Emissions
- IEC 61000-6-4
- ESD immunity
- IEC 61000-4-2
- Radiated RF immunity
- IEC 61000-4-3
- Conducted RF Immunity
- IEC 61000-4-6 (Not applicable: USB is a temporary programming port.)
Technical documents (1)
Key features
- 8 MB user memory and 4 MB safety memory
- Ships with a pre-installed 1 GB SD card (1784-SD1)
- Two slots wide; both modules needed, each one slot
- Standard and safety options: EtherNet/IP, ControlNet, DeviceNet
- Operates at 0 to 60 °C, open-style enclosure
About the Allen-Bradley 1756-L73S
The Allen-Bradley 1756-L73S is a chassis-based controller that Rockwell Automation names the Logix 5573S Automation Controller 8M/4M. Rockwell's technical data 1756-TD001 lists 8 MB of user memory, 4 MB of safety memory and 0.98 MB of I/O memory, with a maximum of 128,000 total I/O. Nonvolatile storage is a 1 GB Secure Digital (SD) card (1784-SD1) that ships pre-installed in the controller. Rockwell lists the lifecycle status as Active Mature.
What is the 1756-L73S used for?
The 1756-L73S runs the control program in a ControlLogix chassis and can be fitted in any slot of the listed 1756 chassis. Rockwell's data describes it as a GuardLogix controller: the safety task supports Ladder Diagram only, while standard tasks support Ladder Diagram, Structured Text, Function Block Diagram and Sequential Function Chart. It offers standard and safety communication over EtherNet/IP, ControlNet and DeviceNet.
Lifecycle and successor
Active.
Before you order
What to photograph or confirm so the right unit is quoted.
Check that the catalog number on the module label reads 1756-L73S, and note the series letter and firmware revision printed on the same label. Send us a photo of the label if you want us to confirm the part before ordering.
Alternatives for 1756-L73S
The manufacturer’s named successor and other parts in the same family. None is a drop-in replacement without checking wiring, I/O and configuration for your installation.
| Product | Manufacturer | Type | Lifecycle | Relationship | Qty Available | Price | Action |
|---|---|---|---|---|---|---|---|
| Allen-Bradley 1756-L71ControlLogix 2 MB controller with SD card | Allen-Bradley | ControlLogix controller | Active | Same family | On Request | On request | View › |
| Allen-Bradley 1756-L72ControlLogix 4 MB controller, 1-port USB | Allen-Bradley | ControlLogix controller | Active | Same family | On Request | On request | View › |
| Allen-Bradley 1756-L73ControlLogix 8 MB controller, 1-port USB | Allen-Bradley | ControlLogix controller | Active | Same family | On Request | On request | View › |
| Allen-Bradley 1756-L74ControlLogix 16 MB controller, USB port | Allen-Bradley | ControlLogix controller | Active | Same family | On Request | On request | View › |
| Allen-Bradley 1756-L75ControlLogix 32 MB controller, USB port | Allen-Bradley | ControlLogix controller | Active | Same family | On Request | On request | View › |
| Allen-Bradley 1756-L73XTControlLogix 8MB Controller L7XT | Allen-Bradley | ControlLogix controller | Active | Same family | On Request | On request | View › |
| Allen-Bradley 1756-L71SLogix 5571S safety controller, 2 MB user memory | Allen-Bradley | GuardLogix safety controller | Active | Same family | On Request | On request | View › |
| Allen-Bradley 1756-L72SGuardLogix 5572S controller, 4 MB user memory | Allen-Bradley | GuardLogix safety controller | Active | Same family | On Request | On request | View › |
| Allen-Bradley 1756-L7SPLogix L7SP SIL 3 PLe safety partner | Allen-Bradley | Safety partner module | Active | Same family | On Request | On request | View › |
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