Bently Nevada 21000-28-05-00-050-03-02 Proximity Probe

21000-28-05-00-050-03-02 — Stop the Clock on Your Downtime. Ship Today.

Every hour a turbine or compressor train sits idle costs real money — production losses, penalty clauses, and the pressure of an entire maintenance crew waiting on one part. The Bently Nevada 21000-28-05-00-050-03-02 Proximity Probe Housing Assembly is on our shelf in Xiamen right now. We cut the lead time from weeks to days so your machine gets back online before the next shift change.

This is not a grey-market substitute. It is a 100% original Bently Nevada 3300 XL Series proximity probe housing assembly — the same part your OEM documentation specifies, the same eddy-current sensing element your monitor was calibrated against. No re-ranging. No re-commissioning. Pull the failed probe, torque the replacement to spec, and restore protection.

URGENT REQUIREMENT? Contact: [email protected] | WhatsApp: +86 18359268345

Quick Technical Datasheet

Troubleshooting & Replacement Tips

Common fault signatures that point to a failed 21000-28-05-00-050-03-02:

• Alert/Danger on radial channel with no process change — gap voltage has drifted outside the –10 V ±1 V nominal. Measure DC output at the Proximitor terminal strip. If it reads near –24 V (open circuit) or 0 V (short), the probe coil or cable is the culprit.
• Intermittent OK/Not-OK relay chatter — flex fatigue at the probe-to-extension cable junction. Inspect the armored jacket at the first bend point. A hairline crack in the shield braid causes noise that mimics real vibration.
• Flat-line waveform on dynamic channel — probe tip contamination (scale, rust, or non-conductive coating on the target). Clean the target face and re-gap before condemning the probe.
• Fault code 88 / System OK LED off on 3500/42M monitor — Proximitor not receiving –24 VDC supply. Check fuse F1 on the I/O module before pulling the probe.

Step-by-step replacement procedure (3300 XL, 8 mm probe):

1. Bypass the protection channel — place the affected channel in Bypass mode at the 3500 rack front panel to suppress spurious trips during the swap.
2. De-energise and lock out the –24 VDC supply to the Proximitor sensor before disconnecting any cables.
3. Record the existing gap voltage from the monitor display or the Proximitor test point (TP1). Target: –10.0 V ±0.5 V for a 1.0 mm air gap on steel target.
4. Remove the probe — counter-clockwise on the M10 × 1 thread. Use the flat on the housing body, never grip the cable. Torque spec on reinstall: 14 N·m (10 ft·lb).
5. Install the 21000-28-05-00-050-03-02 — thread in finger-tight, then set gap with a non-ferrous feeler gauge. Nominal gap: 1.0 mm (40 mil). Lock the jam nut.
6. Reconnect the extension cable (330130 series) — verify the BNC or TNC connector seats fully and the locking ring clicks. A partial connection is the single most common cause of post-replacement faults.
7. Re-energise the Proximitor and confirm gap voltage returns to –10.0 V ±0.5 V. Adjust gap in 0.1 mm increments if needed.
8. Remove Bypass and confirm the channel returns to OK state. Log the as-left gap voltage in your maintenance record.

Configuration notes: The 21000-28-05-00-050-03-02 is a passive probe — there are no DIP switches, no firmware, and no address configuration. The Proximitor sensor (330180/330181) handles signal conditioning. Ensure the Proximitor scale factor is set to 200 mV/mil in the 3500 monitor configuration if you are replacing a probe that was previously set to a different sensitivity.

Reliability in Harsh Conditions

Rotating machinery environments are unforgiving. The 21000-28-05-00-050-03-02 is engineered to operate continuously where most instrumentation fails:

• Vibration & shock: The 316 stainless steel housing and armored cable assembly are rated to withstand 20 g shock and 5 g continuous vibration per IEC 60068-2-6. In practice, this means the probe survives the same mechanical punishment as the bearing housing it monitors.
• Thermal cycling: With a –40 °C to +177 °C operating range, the probe handles both arctic cold-start conditions and the radiant heat of a gas turbine exhaust casing without drift in sensitivity. The coil potting compound is selected specifically to resist thermal expansion mismatch.
• Chemical & moisture ingress: The IP67-rated connector and hermetically sealed probe tip resist hydrocarbon vapors, steam, and wash-down water. In offshore and petrochemical installations where salt fog and condensation are daily realities, this rating is not a marketing claim — it is a maintenance interval multiplier.
• EMI immunity: The coaxial cable construction and Faraday-shielded housing reject high-frequency electrical noise from VFDs, switchgear, and welding equipment that would corrupt the millivolt-level signals of lesser sensors.

Global Express Logistics

Our Xiamen warehouse is positioned 40 minutes from Xiamen Gaoqi International Airport (XMN), a major DHL and FedEx hub for South China exports. Here is what that means for your timeline:

• Order confirmed before 14:00 CST → same-day pick, pack, and handover to carrier.
• DHL Express Worldwide — transit time 2–4 business days to Europe, Middle East, and Southeast Asia; 3–5 days to North America.
• FedEx International Priority — available as an alternative for US and Canadian destinations with guaranteed delivery windows.
• Documentation package included with every shipment: commercial invoice, packing list, HS code 9031.80 declaration, and Certificate of Conformance. Customs clearance delays caused by missing paperwork are eliminated before the box leaves our dock.
• Tracking is shared via email within 2 hours of carrier pickup. For urgent shutdowns, WhatsApp updates are available on request.
• Bulk orders (>5 units): contact us for consolidated air-freight pricing and priority allocation from stock.

Contact Information

Email: [email protected]
WhatsApp: +86 18359268345
Web: siemensplc.com
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