Guard I/O 1791ES and 1791DS Repair

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The Guard I/O 1791ES and 1791DS module series is a series of Allen-Bradley Guard I/O Ethernet/IP and DeviceNet safety modules that help to implement CIP safety protocol extensions over the DeviceNet and Ethernet/IP networks. In addition to providing fail-safe communication between safety devices and controllers on the DeviceNet/Ethernet network that meets safety requirements up to Safety Integrity Level 3 (SIL 3), the Guard I/O 1791ES and 1791DS module series devices can be used to design and create safety-control systems for the processing and communication of safety data on both networks. The Guard I/O 1791ES and 1791DS modules are DC powered devices with an input range of 18 to 30 Volts DC, and a maximum current rating of 8 Amps. These devices have current sinking-type safety inputs that serve as interfaces for emergency stop pushbuttons, gate switches, and safety light curtains.

The Guard I/O 1791ES and 1791DS modules support both single and dual-channel modes that allow for use in Safety Categories 2, 3, and 4. They all have time-setting switches that allow for the monitoring of logical discrepancies between 2 channels. The Guard I/O 1791ES and 1791DS modules have 4 dual-channel bipolar safety outputs that are the current-sinking/current sourcing type with 2 Amps maximum input current ratings, and these safety outputs can only be controlled by safety controllers. The Guard I/O 1791ES and 1791DS modules have current sourcing pulse test outputs that can be used to detect short-circuit conditions on the safety inputs, and these outputs can be configured for standard outputs. These devices collect both I/O and I/O status data for the monitoring of I/O operation, and the 1791DS (only) devices have password-protected security that protects the configuration data. The Guard I/O 1791ES and 1791DS modules are DIN Rail mounted, and they come with removable I/O connectors that support mechanical keying.