Description
Key Technical Specifications
- System Platform: Bently Nevada 1900 Series
- Vibration Inputs: 4 Channels (Proximity, Velocity, Accelerometer)
- Temperature Inputs: 4 Channels (E, J, K, T Thermocouples / RTDs)
- Relay Outputs: 6 Configurable (Alert & Danger with voting logic)
- Analog Outputs: 4 x 4-20 mA Recorder Outputs
- Buffered Outputs: 4 Dedicated Sensor Outputs + 1 Display Output
- Communication: Modbus TCP/RTU (Ethernet / RS232 / RS485)
- Power Supply: 18 to 36 VDC (External 110/220 VAC adapter option)
- Operating Temperature: -20°C to +70°C (-4°F to +158°F)
- Display: Optional Front-Mount or Remote (up to 75m / 250 ft)
- Condition: New Surplus / Refurbished
Product Introduction
Not every fan, pump, or auxiliary compressor justifies a $50,000 3500-series rack. The 1900/65A (167699-02) is Bently’s answer to protecting balance-of-plant assets without bleeding the maintenance budget dry. It’s a self-contained, 4-channel monitor that takes raw signals from eddy current probes, velocity sensors, or accelerometers, processes them, and triggers relays or 4-20mA loops directly. No backplane, no chassis, no rack.
Why keep these in the warehouse? Because they are incredibly flexible. You can configure each channel via software to measure radial vibration, axial displacement, or even temperature. It packs 6 relays with voting logic, meaning a single sensor won’t trip a critical pump if the other three disagree. Honestly, for OEM skids or remote water plants, this is the exact right tool. Just remember: it’s a standalone unit. If you want System 1 software integration, make sure your specific unit has the Modbus gateway option installed.
Troubleshooting Quick Reference
| Fault | Cause | Relevancy | Quick Check | Fix |
|---|---|---|---|---|
| Value Jumps / Spikes | Ground Loop / Noise | 80% | Check sensor cable shielding | Verify single-point shield ground. |
| Reading Too High/Low | Config Mismatch | 75% | Open 1900 Config Software | Verify sensor type and scaling. |
| Comm Dropouts | Modbus Timeout | 60% | Ping module via Ethernet | Check IP subnet and gateway config. |
| Relay Chattering | Filter Setting Too Low | 50% | Review high/low pass filter config | Increase filter poles or adjust time constant. |
| No 4-20mA Output | Power / Config | 90% | Measure 24V loop power | Verify channel is mapped to analog out. |
BENTLY 167699-02 1900/65A
Application Scenarios & Pain Points
- Cooling Tower Fans: High ambient heat and humidity. Standard transmitters drift. The 1900/65A processes the raw proximity signal locally, keeping the 4-20mA run clean back to the DCS.
- Chemical Transfer Pumps: Cavitation causes high-frequency acceleration spikes. You need local processing to filter out the noise before it trips the PLC. This unit handles up to 8-pole filtering natively.
- Remote Water Booster Stations: No local control room. Mount the optional display up to 250 feet away on the fence line so operators can read vibration without opening the NEMA 4X panel.
Compatible Replacement Models
- ✅ Drop-in Replacement: 1900/65A-02 (167699-02). Exact match. Same I/O count, same Modbus mapping. Cost: ~3,000–5,000 surplus.
- ⚠️ Software Compatible: 1900/65A-01. Same hardware, different factory option code. Requires downloading your existing config file via Ethernet. Labor: 30 mins + loop check.
- ❌ Hardware Incompatible: 3500/42M. Rack-mounted system module. Different power, different wiring, requires 3500 rack and keyphasor. Do not substitute unless upgrading the entire protection scheme.
