Product Overview

The Allen-Bradley 1756-L61S is a GuardLogix safety controller for ControlLogix systems. This processor has 2 MB of standard memory. It also has 1 MB of dedicated safety memory. The module works in 1756 ControlLogix or 1768 control systems. You can install multiple controllers in one chassis. The controller monitors I/O across the backplane and over networks. A conformal coating protects against harsh environments.

For inquiries, contact us at +86 158 8020 0923 (WhatsApp).

Part Number Breakdown (Tree Structure)

• 1756 → Series Family
  • ControlLogix platform
  • Allen-Bradley / Rockwell Automation
• L → Product Type
  • Logix controller (processor)
• 61 → Memory Size
  • 2 MB standard memory
  • 1 MB safety memory
• S → Safety Version
  • GuardLogix safety controller

Memory Specifications

• User Memory (Standard): 2 MB
• Safety Memory: 1 MB
• I/O Memory: 478 KB

I/O Capacity

• Maximum Digital I/O: 128,000 points
• Maximum Analog I/O: 4,000 points
• Total Maximum I/O: 128,000 points

Power Consumption

• Current Draw (5.1 VDC): 1200 milliamps (1.2 A)
• Current Draw (24 VDC): 14 milliamps (0.014 A)
• Power Dissipation: 3.5 Watts
• Thermal Dissipation: 11.9 BTU per hour

Isolation and Protection

• Isolation Voltage: 30 Volts continuous
• Conformal Coating: Yes (polymer protective layer)
• Coating protects against contaminants and humidity.
• Coating extends product life in harsh environments.
• Enclosure Type: None (open-style)

Network Support

• DeviceNet
• ControlNet
• EtherNet/IP (via rooted Ethernet port)
• Direct connection to Ethernet devices and networks

System Architecture Features

• Place multiple controllers in one chassis.
• Monitor I/O across the ControlLogix backplane.
• Monitor I/O over network links.
• Install communication interface modules in local chassis.
• Use as part of 1756 or 1768 control systems.

Conformal Coating Benefits

• Thin polymer layer protects circuit boards.
• Blocks moisture and corrosive contaminants.
• Prevents dust and pollutant damage.
• Extends product life significantly.
• Ideal for harsh industrial environments.

Product Lifecycle Status

• Status: Discontinued / Obsolete
• Limited stock available for replacement needs.
• Check system compatibility before ordering.

Installation Guide

• Turn off all power before installation.
• Insert the Allen-Bradley 1756-L61S into any slot of the chassis.
• Press firmly until the controller seats in the backplane.
• Secure the module with the retaining screws (if any).
• Connect to Ethernet using the rooted port.
• Install communication modules for DeviceNet or ControlNet.
• Apply power and check controller status LED.
• Download your safety program using RSLogix 5000 software.

Programming Requirements

• Requires RSLogix 5000 software (version 16 or later).
• Use GuardLogix safety add-on instructions.
• Separate safety task for safety-related logic.
• Standard task for non-safety control logic.

Maintenance Tips

• Check LED indicators for fault conditions.
• Monitor battery status annually (if battery used).
• Keep conformal coating intact for protection.
• Do not clean with solvents that remove coating.
• Perform regular program backups.
• Replace controller if safety faults persist.

Troubleshooting Tips

• If OK LED is red, check power supply and backplane.
• If FORCE LED is on, forces are active in program.
• If I/O LED flashes, check I/O module connections.
• Use RSLogix 5000 to view fault codes.
• Check safety partner status for dual-processor configurations.

Package Contents

• One Allen-Bradley 1756-L61S GuardLogix controller
• One product label
• Communication modules not included (order separately)

Warranty and Shipping

• 12 months factory warranty from shipment date.
• Warranty covers manufacturing defects only.
• Physical damage or overvoltage voids the warranty.
• Shipping options: FedEx, UPS, DHL.
• Tracking number provided after shipment.

Frequently Asked Questions (FAQ)

Q1: How much memory does the 1756-L61S have?

The Allen-Bradley 1756-L61S has 2 MB of standard user memory. It also has 1 MB of dedicated safety memory. I/O memory is 478 KB. Total memory is sufficient for most safety applications.

Q2: What is the difference between 1756-L61 and 1756-L61S?

The 1756-L61 is a standard ControlLogix controller. The 1756-L61S is a GuardLogix safety controller. The S version has 1 MB of safety memory. Use the S version for safety-rated applications.

Q3: Does this controller have conformal coating?

Yes, the 1756-L61S has a conformal coating. This polymer layer protects against moisture and contaminants. It extends product life in harsh and corrosive environments.

Q4: What is the maximum I/O for the 1756-L61S?

Maximum digital I/O is 128,000 points. Maximum analog I/O is 4,000 points. Total maximum I/O is 128,000 points. This supports large distributed control systems.

Q5: Is the 1756-L61S still in production?

No, this product is discontinued and obsolete. We have limited new and original stock available. Order soon for replacement needs in existing systems.

Buying Guide

When you buy a Allen-Bradley 1756-L61S GuardLogix controller, follow these tips. First, verify your safety memory requirement. This controller has 1 MB safety memory. Second, check your standard memory need. This controller has 2 MB standard memory. Third, count your I/O points. This controller supports 128,000 digital I/O. Fourth, consider your network type. Use DeviceNet, ControlNet, or EtherNet/IP. Fifth, verify your software version. RSLogix 5000 version 16 or later is required. Sixth, check your chassis compatibility. Use standard ControlLogix 1756 chassis. Seventh, consider conformal coating needs. This controller works in harsh environments. Eighth, plan for discontinued status. Buy spares while available. Ninth, review warranty terms. We offer 12 months coverage. Tenth, choose your shipping method. We use FedEx, UPS, and DHL. Finally, test the controller in a non-production chassis before deployment.

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