Tutto sui PLC: la CPU
A practical engineering guide to PLC CPU operation, from deterministic scan cycles and I/O image tables to memory, communications, diagnostics, redundancy, processor sizing, and reliable system...
The Allen-Bradley 1756-LSP serves as a dedicated, hardware-isolated redundant co-processor within safety-instrumented systems to execute multi-channel diagnostic and lockstep safety verification logic. Operating as a specialized safety partner module paired with a primary controller, this unit establishes an isolated secondary execution environment to safely handle safety-related functions up to and including SIL 3 and Performance Level e requirements. The device contains no localized user memory for standard operations; instead, its configuration parameters, clock operations, and safety memory structures are bound to and managed by the corresponding master unit.
| Parameter | Specification |
|---|---|
| Manufacturer | Allen-Bradley / Rockwell Automation |
| Model Part Number | 1756-LSP |
| Module Type | Safety Partner Module |
| Series | GuardLogix 5560 |
| Compatible Primary Controllers | 1756-L61S, 1756-L62S, 1756-L63S |
| Supported Connections | 250 |
| User / Standard Memory | N/A (None) |
| Current Draw @ 5.1V DC | 1200 mA |
| Current Draw @ 24V DC | 14 mA |
| Power Dissipation | 3.5 W |
| Thermal Dissipation | 11.9 BTU/hr |
| Isolation Voltage | 30V Continuous (Basic Insulation, Type-tested from RS-232 port-to-system at 720V DC for 60 seconds) |
| Local Serial Interface | 1 x RS-232 port |
| Backup Battery Element | 1756-BA2 (0.50 g lithium assembly) |
| Chassis Slot Width Allocation | 1 slot (Requires adjacent slot for primary module; 2 slots total for operation) |
| Chassis Compatibility | 1756-A4, 1756-A7, 1756-A10, 1756-A13, 1756-A17 |
| Power Supply Compatibility | 1756-PA50, 1756-PA72, 1756-PA75, 1756-PB50, 1756-PB72, 1756-PB75 |
| Enclosure Class | None (Open-Style) |
| Operating Temperature Range | 0 Celsius to 60 Celsius |
| Non-Operating Temperature | -40 Celsius to 85 Celsius |
| Relative Environmental Humidity | 5-95% non-condensing |
| Mechanical Shock (Operating) | 30 g |
| Mechanical Shock (Non-Operating) | 50 g |
| Vibration Stress Tolerance | 2 g at 10-500 Hz |
| Shipping Weight (Calculated) | 0.75 lbs (0.34 kg) |
| Physical Dimensions (Calculated) | 27 x 17 x 7 cm (10.63 x 6.69 x 2.76 in.) |
The 1756-LSP safety partner is structurally locked to the GuardLogix 5560 architecture. It functions solely when paired alongside a 1756-L61S, 1756-L62S, or 1756-L63S safety controller. Attempting to link this safety module with standard ControlLogix non-safety processors or newer ControlLogix 5570/5580 systems will result in backplane verification errors and halt CPU configuration loading.
A major engineering pitfall occurs when calculating available workspace inside open enclosures. If the safety partner is not placed in the slot directly to the right of its primary controller, the pair cannot satisfy structural SIL 3 requirements, causing a total breakdown of safety loop integrity. Furthermore, because this card relies completely on the master controller for communication links and configuration parameters, its onboard RS-232 port cannot be independently utilized for broad network mapping or logic modification. Ensure the onboard 1756-BA2 lithium battery cell is monitored regularly; low energy levels can corrupt clock operations during complete system power blackouts.
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The Allen-Bradley 1756-LSP serves as a dedicated, hardware-isolated redundant co-processor within safety-instrumented systems to execute multi-channel diagnostic and lockstep safety verification logic. Operating as a specialized safety partner module paired with a primary controller, this unit establishes an isolated secondary execution environment to safely handle safety-related functions up to and including SIL 3 and Performance Level e requirements. The device contains no localized user memory for standard operations; instead, its configuration parameters, clock operations, and safety memory structures are bound to and managed by the corresponding master unit.
| Parameter | Specification |
|---|---|
| Manufacturer | Allen-Bradley / Rockwell Automation |
| Model Part Number | 1756-LSP |
| Module Type | Safety Partner Module |
| Series | GuardLogix 5560 |
| Compatible Primary Controllers | 1756-L61S, 1756-L62S, 1756-L63S |
| Supported Connections | 250 |
| User / Standard Memory | N/A (None) |
| Current Draw @ 5.1V DC | 1200 mA |
| Current Draw @ 24V DC | 14 mA |
| Power Dissipation | 3.5 W |
| Thermal Dissipation | 11.9 BTU/hr |
| Isolation Voltage | 30V Continuous (Basic Insulation, Type-tested from RS-232 port-to-system at 720V DC for 60 seconds) |
| Local Serial Interface | 1 x RS-232 port |
| Backup Battery Element | 1756-BA2 (0.50 g lithium assembly) |
| Chassis Slot Width Allocation | 1 slot (Requires adjacent slot for primary module; 2 slots total for operation) |
| Chassis Compatibility | 1756-A4, 1756-A7, 1756-A10, 1756-A13, 1756-A17 |
| Power Supply Compatibility | 1756-PA50, 1756-PA72, 1756-PA75, 1756-PB50, 1756-PB72, 1756-PB75 |
| Enclosure Class | None (Open-Style) |
| Operating Temperature Range | 0 Celsius to 60 Celsius |
| Non-Operating Temperature | -40 Celsius to 85 Celsius |
| Relative Environmental Humidity | 5-95% non-condensing |
| Mechanical Shock (Operating) | 30 g |
| Mechanical Shock (Non-Operating) | 50 g |
| Vibration Stress Tolerance | 2 g at 10-500 Hz |
| Shipping Weight (Calculated) | 0.75 lbs (0.34 kg) |
| Physical Dimensions (Calculated) | 27 x 17 x 7 cm (10.63 x 6.69 x 2.76 in.) |
The 1756-LSP safety partner is structurally locked to the GuardLogix 5560 architecture. It functions solely when paired alongside a 1756-L61S, 1756-L62S, or 1756-L63S safety controller. Attempting to link this safety module with standard ControlLogix non-safety processors or newer ControlLogix 5570/5580 systems will result in backplane verification errors and halt CPU configuration loading.
A major engineering pitfall occurs when calculating available workspace inside open enclosures. If the safety partner is not placed in the slot directly to the right of its primary controller, the pair cannot satisfy structural SIL 3 requirements, causing a total breakdown of safety loop integrity. Furthermore, because this card relies completely on the master controller for communication links and configuration parameters, its onboard RS-232 port cannot be independently utilized for broad network mapping or logic modification. Ensure the onboard 1756-BA2 lithium battery cell is monitored regularly; low energy levels can corrupt clock operations during complete system power blackouts.
Global Express Shipping
Returns & Warranty
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For full eligibility, restocking fees, and international return details, please view our official Refund & Return Policy .
| Color pattern |
Black
|
| Country of origin |
United States
|
| Power source |
DC Power
Battery-powered
|