The 1756-L61S is a GuardLogix safety controller module that provides integrated safety and standard control within the ControlLogix system architecture. The 1756-L61S mounts into any available slot of a standard ControlLogix I/O chassis and can execute control logic, monitor system operations, and manage communication across the backplane and network links. Featuring a conformal coating to protect internal circuitry from moisture and environmental contaminants, the 1756-L61S provides high-capacity process and safety execution capabilities for demanding industrial applications.
Open-style enclosure with protective conformal coating against harsh environmental factors.
Direct backplane communication supporting local chassis I/O monitoring and network interface modules.
High I/O processing capability supporting up to 128,000 digital and 4,000 analog I/O points.
Embedded RS-232 serial communication port for local programming and interfacing.
Applications
Integrated machine and functional safety control systems
Assembly and automotive manufacturing lines
Material handling and high-speed packaging machinery
Process control requiring fail-safe logic and SIL-rated monitoring
Technical Specifications
Parameter
Value
Manufacturer
Allen-Bradley
Part Number
1756-L61S
Module Type
GuardLogix Controller
User Memory
2 MB
I/O Memory
478 KB
Maximum Digital I/O
128,000
Maximum Analog I/O
4,000
Maximum Total I/O
128,000
Current Draw (5.1V DC)
1200 mA
Current Draw (24V DC)
14 mA
Power Dissipation
3.5 W
Thermal Dissipation
11.9 BTU per hour
Isolation Voltage
30V Continuous
Enclosure Type
None (Open-Style)
Weight
0.34 kg (0.75 lbs)
UPC
612598321742
UNSPSC
32151705
Installation Guidelines
Chassis Alignment: Align the module card guide with the top and bottom chassis slots and slide the unit firmly into place until the locking tabs snap.
Cooling and Ventilation: Ensure sufficient space around the chassis enclosure to maintain proper airflow and prevent ambient temperatures from exceeding maximum rated operational limits.
Grounding: Verify that the 1756 chassis is properly grounded to the system enclosure using a low-impedance copper ground wire to mitigate electromagnetic interference (EMI).
Network Wiring: When utilizing communication interface modules alongside the controller, route all communication cables away from high-voltage power lines and noisy equipment.
FAQ
What memory capacity does the module offer for safety and standard tasks?
The device provides 2 MB of user memory along with 478 KB of dedicated I/O memory.
What is the continuous isolation voltage for this controller?
The continuous isolation voltage is rated at 30V continuous.
What power dissipation and thermal load does the unit generate?
The device has a power dissipation of 3.5 Watts and generates a thermal dissipation of 11.9 BTU per hour.
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