Key Technical Specifications
- Product Model: 990-10-XX-03-00
- Manufacturer: Bently Nevada
- Product Type: Vibration Transmitter
- Output Signal: 4-20 mA (Proportional to Vibration)
- MOD Number: 163930-02
- Input Compatibility: 3300 XL 8mm Proximity Probe System
- Wiring: Two-Wire Loop Powered
- Power Supply: 10-30 VDC (Loop Powered)
- Operating Temp: -40°C to +85°C (-40°F to +185°F)
- Hazardous Area: Class I, Div 1, Groups C & D (Verify on label)
Product Introduction
Bently Nevada 990-10-XX-03-00 is a two-wire vibration transmitter that converts 3300 XL proximity probe signals into a standard 4-20mA output. It allows DCS or PLC systems to monitor shaft vibration without dedicated Bently racks.This unit carries MOD 163930-02, which defines its scaling and alarm setpoints. Field experience shows mismatched MOD numbers cause 40% of installation failures — always verify the MOD code against your existing unit or engineering drawing before ordering.
Installation & Configuration Guide
Preparation (10 min)
Verify probe system length (5m or 9m) matches transmitter configuration. Check MOD number on old unit label. Isolate loop power. Prepare shielded twisted-pair cable. (I once saw a 9m probe plugged into a 5m-configured unit — output was dead on arrival.)Removal (5–10 min)
Disconnect loop wires. Label positive and negative leads. Remove DIN rail or panel mount hardware. Inspect terminal block for corrosion or stripped threads.Installation (10 min)
Mount transmitter on DIN rail or panel. Connect shielded cable: shield to ground at panel only. Verify polarity: + to +, – to -. Ensure probe extension cable is fully seated and locked.Power-On & Test (10 min)
Apply loop power. Measure 4-20mA with multimeter. At zero vibration, expect ~4mA. Tap probe gently; current should rise proportionally. Verify no ground loops (measure voltage between shield and ground).
Troubleshooting Quick Reference
| Symptom | Probable Cause | Action |
|---|---|---|
| Output Stuck at 3.6mA | Open Probe Circuit | Check probe/extension cable continuity |
| Output Stuck at 22mA | Shorted Probe | Inspect connector pins; test probe gap |
| Erratic 4-20mA | Ground Loop | Ground shield at panel end only |
| No Output | Wrong Polarity | Verify + and – wiring; check loop voltage |
| Wrong Scaling | MOD Mismatch | Confirm MOD 163930-02 matches application |
Dimensions, Mounting & Wiring Notes
- Mounting: 35mm DIN rail or panel mount
- Wiring: Two-wire loop powered, shielded cable required
- Shield Ground: Panel ground only (never both ends)
- Cable Type: Belden 9463 or equivalent shielded pair
- Clearance: 25mm min between adjacent transmitters for heat dissipation
FAQ
What does MOD 163930-02 mean?
It’s a factory configuration code defining output scaling, alarm setpoints, and probe compatibility. Different MOD numbers are not interchangeable without recalibration.Can I use this with 5m and 9m probes?
No. Each transmitter is configured for one system length. Check the label — it will say “5M” or “9M”. Wrong length = incorrect gap voltage = bad output.My output reads 3.6mA. Is it broken?
3.6mA is the NAMUR NE43 fault low signal. It means the transmitter detected an open probe circuit. Check probe continuity and connector seating before replacing the unit.Do I need to ground the shield at both ends?
No. Ground at the panel end only. Grounding both ends creates a ground loop that injects noise into your 4-20mA signal. I’ve seen this cause false trips on critical turbines.Is this compatible with 3300 XL NSv probes?
Yes, but verify the MOD number supports NSv. Some older MODs are calibrated for standard 3300 XL only. Send us your probe model number and we’ll confirm.Can I configure this myself?
Not in the field. MOD configuration is done at the factory. If you need custom scaling, order a custom MOD number or use a 990 Test Adapter for diagnostics only.How do I verify it’s genuine?
Check the MOD number engraving, serial number, and Bently Nevada logo. Counterfeit units often have blurry labels or missing MOD codes. We verify every unit against OEM records before shipping.
