Description
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.
Key Features
- Four independent, programmable Single-Pole Double-Throw (SPDT) relay channels.
- Compatible with standard 3500 series backplanes and slot structures.
- Supports "Normally Energized" (NE) and "Normally De-energized" (NDE) configurations.
- Extensive voting logic capability, allowing logical combinations of Alert and Danger statuses from multiple monitor channels.
- Equipped with onboard health monitoring to ensure relay drive circuitry is functional.
- CN designated option indicating compliance with specific country approval requirements.
Applications
- Executive emergency machinery shutdown systems for steam turbines, gas turbines, and compressors.
- Integration with Distributed Control Systems (DCS) and Programmable Logic Controllers (PLC) for hardwired alarm annunciation.
- Actuating local hazardous area alarm horns, beacons, and auxiliary indicators.
- Interlocking critical process control loops based on physical machinery vibration boundaries.
Technical Specifications
| 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 |
Connections and Interfaces
| 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. |
Empirical Engineering Insights
Alternative Models & Compatibility
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.
Application Pitfalls & Engineering Notes
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.
Commissioning & Wiring Tips
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.
Installation Guidelines
CRITICAL WARNING: Hazardous voltages may be present on the relay contact terminals. Disconnect and lock out all external power sources supplying the relay contacts before servicing, removing, or replacing the module. Failure to de-energize external wiring can result in severe electrical shock, component destruction, or accidental machinery trip.
1
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).
2
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.
3
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.
4
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.