Implementing 3-Switch XOR Ladder Logic with Internal Bit
Implement a 3-SPST switch XOR light circuit in LogixPro or RSLogix 500 using an internal relay bit. Includes truth tables, boolean equations, and verified.
To drive external machinery control loops and execute critical protective safety shutdowns, the Bently Nevada 3500/32-01-CN integrates four fully programmable relay outputs into the 3500 series machinery protection rack. This full-height module accepts input logic from other monitors in the rack to control independent, single-pole double-throw (SPDT) relays. Highly configured for critical safety interlocking, the module provides reliable contact state changes based on alarm status and user-defined voting logic designed in the 3500 Rack Configuration Software.
| Parameter | Value / Specification |
|---|---|
| Manufacturer | Bently Nevada |
| Model Number | 3500/32-01-CN |
| Module Type | 4-Channel Relay Output Module |
| Number of Channels | 4 SPDT Relays |
| Relay Contact Rating (Resistive) | 5 A @ 120 Vac / 240 Vac (Max); 5 A @ 30 Vdc (Max) |
| Minimum Contact Load | 100 mA @ 5 Vdc |
| Agency Approvals Option | CN (Country Specific Approvals) |
| Mounting Location | Any full-height slot except Power Supply and Rack Interface Module slots |
| Country of Origin | USA |
| Shipping Weight (Calculated) | 2.0 kg |
| Terminal Designation | Functional Assignment |
|---|---|
| NO (Normally Open) | Closes connection to Common when relay coil is energized. |
| NC (Normally Closed) | Opens connection to Common when relay coil is energized. |
| COM (Common) | Common reference pole for the respective channel's SPDT contact circuit. |
While the 3500 system also supports a 16-Channel Relay Module (the 3500/33), the 4-Channel 3500/32 provides robust SPDT Form-C outputs which are typically preferred for direct trip solenoid activation. Ensure that the 3500/32 firmware revision is compatible with your Rack Interface Module (RIM) firmware version before attempting slot allocation changes.
When switching highly inductive AC loads (such as heavy solenoid valves or larger motor starters), installing external arc-suppression (RC snubbers) across the contacts is critical to prevent contact erosion and premature welding. Operating close to the 5 A limit without suppression can degrade relay lifespans and lead to dangerous "fail-to-open" states.
Always configure the "OK Relay" function correctly inside the configuration panel. Under normal running conditions, we recommend operating safety shutdown loops in a Normally Energized (NE) de-energize-to-trip mode. This ensures that a total loss of instrument control power automatically triggers the safe state of the machinery loop.
Power down the 3500 rack system if hot-swapping is not permitted by plant safety procedures. (The 3500 system supports hot-swapping under specific restricted environmental conditions).
Insert the main 3500/32-01-CN module into the front of the rack, sliding it along the guide rails until it is firmly seated in the backplane connector. Tighten the two securing screws on the front panel.
Mount the corresponding 4-channel relay I/O module into the back of the rack directly behind the front-facing slot. Secure it with its chassis panel screws.
Connect your alarm loop field wiring to the rear terminal block using proper wire-end ferrules to guarantee mechanical integrity and prevent short-circuiting between adjacent contact terminals.
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To drive external machinery control loops and execute critical protective safety shutdowns, the Bently Nevada 3500/32-01-CN integrates four fully programmable relay outputs into the 3500 series machinery protection rack. This full-height module accepts input logic from other monitors in the rack to control independent, single-pole double-throw (SPDT) relays. Highly configured for critical safety interlocking, the module provides reliable contact state changes based on alarm status and user-defined voting logic designed in the 3500 Rack Configuration Software.
| Parameter | Value / Specification |
|---|---|
| Manufacturer | Bently Nevada |
| Model Number | 3500/32-01-CN |
| Module Type | 4-Channel Relay Output Module |
| Number of Channels | 4 SPDT Relays |
| Relay Contact Rating (Resistive) | 5 A @ 120 Vac / 240 Vac (Max); 5 A @ 30 Vdc (Max) |
| Minimum Contact Load | 100 mA @ 5 Vdc |
| Agency Approvals Option | CN (Country Specific Approvals) |
| Mounting Location | Any full-height slot except Power Supply and Rack Interface Module slots |
| Country of Origin | USA |
| Shipping Weight (Calculated) | 2.0 kg |
| Terminal Designation | Functional Assignment |
|---|---|
| NO (Normally Open) | Closes connection to Common when relay coil is energized. |
| NC (Normally Closed) | Opens connection to Common when relay coil is energized. |
| COM (Common) | Common reference pole for the respective channel's SPDT contact circuit. |
While the 3500 system also supports a 16-Channel Relay Module (the 3500/33), the 4-Channel 3500/32 provides robust SPDT Form-C outputs which are typically preferred for direct trip solenoid activation. Ensure that the 3500/32 firmware revision is compatible with your Rack Interface Module (RIM) firmware version before attempting slot allocation changes.
When switching highly inductive AC loads (such as heavy solenoid valves or larger motor starters), installing external arc-suppression (RC snubbers) across the contacts is critical to prevent contact erosion and premature welding. Operating close to the 5 A limit without suppression can degrade relay lifespans and lead to dangerous "fail-to-open" states.
Always configure the "OK Relay" function correctly inside the configuration panel. Under normal running conditions, we recommend operating safety shutdown loops in a Normally Energized (NE) de-energize-to-trip mode. This ensures that a total loss of instrument control power automatically triggers the safe state of the machinery loop.
Power down the 3500 rack system if hot-swapping is not permitted by plant safety procedures. (The 3500 system supports hot-swapping under specific restricted environmental conditions).
Insert the main 3500/32-01-CN module into the front of the rack, sliding it along the guide rails until it is firmly seated in the backplane connector. Tighten the two securing screws on the front panel.
Mount the corresponding 4-channel relay I/O module into the back of the rack directly behind the front-facing slot. Secure it with its chassis panel screws.
Connect your alarm loop field wiring to the rear terminal block using proper wire-end ferrules to guarantee mechanical integrity and prevent short-circuiting between adjacent contact terminals.
Global Express Shipping
Returns & Warranty
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| Country of origin |
United States
|