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.
Designed for severe-duty industrial rotating machinery, the Bently Nevada 21000-28-05-15-50-03-02 provides secure mechanical containment and environmental sealing for proximity transducers. This heavy-duty aluminum housing assembly facilitates precise probe positioning and adjustment while maintaining external structural integrity against harsh atmospheric contaminants, oil, and moisture. Engineered as part of critical machinery protection and turbine supervisory instrumentation (TSI) installations, it ensures optimal alignment of the probe relative to the target shaft without requiring the system to be fully depressurized during routine maintenance or adjustment cycles.
| Parameter | Specification Value |
|---|---|
| Manufacturer | Bently Nevada (Baker Hughes) |
| Model Number | 21000-28-05-15-50-03-02 |
| Housing Material | Cast Aluminum |
| Probe Thread Option (-28) | 3/8-24 UNF Thread |
| Conduit Thread Option (-05) | 1/2-14 NPT (Single Conduit Entry) |
| Hazardous Area Approval (-15) | ATEX / IECEx / North American Multi-Approvals |
| Sleeve Length Option (-50) | 5.0 Inches (127 mm) Sleeve Length |
| Fluid Seal Option (-03) | Fluid Seal Option Included (Coaxial Connection Protector) |
| Operating Temperature Range | -40 degC to +100 degC |
| Ingress Protection Rating | IP66 / NEMA 4X equivalent |
| Country of Origin | United States (USA) |
| Shipping Weight (Calculated) | 2.2 kg (4.8 lbs) |
| Package Dimensions (Calculated) | 300 mm x 150 mm x 150 mm |
The Bently Nevada 21000 series aluminum housing is compatible with industry-standard 3300 XL 8mm and 5mm proximity probes. If your installation is located in a highly corrosive marine environment or exposed to continuous acidic washdowns, consider upgrading to the 31000 series housing, which substitutes the cast aluminum body with 316 stainless steel to eliminate galvanic oxidation risks.
When deploying the 21000-28-05-15-50-03-02 on high-temperature steam turbine casings, mechanical engineers must account for thermal expansion of both the machine casing and the 5.0-inch housing sleeve. Operating temperatures above 85 degC can introduce measurable physical expansion in the housing, which directly alters the calibrated sensor gap. Perform dynamic verification tests once the machinery reaches thermal equilibrium.
Ensure that high-temperature thread-locking compound is applied only to the mounting flange adapters and not to the proximity probe's primary adjustment threads. When securing the 1/2-14 NPT conduit connection, use a certified industrial thread sealant (such as PTFE paste or high-grade anti-seize) to guarantee physical compliance with IP66 moisture intrusion ratings and safe explosive atmosphere containment.
Prior to starting any installation, calibration, or maintenance procedure on the housing assembly, verify that the machinery is completely de-energized, locked out, and tagged out (LOTO). Ensure that any localized process pressure within the machine casing has been fully bled and verified at zero atmospheric delta to prevent catastrophic ejection of the probe sleeve during adjustment.
Ensure the mounting surface on the machine casing is clean, completely flat, and free of burrs or remnants of old gaskets.
Thread the proximity probe into the internal 3/8-24 UNF threaded sleeve, making sure the probe cable does not twist or bind.
Calibrate the mechanical gap of the probe using a calibrated digital voltmeter linked to the proximity proximitor sensor output.
Securely tighten the housing sleeve locknut to prevent drift caused by ambient machine vibration, and attach the external conduit line.
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Designed for severe-duty industrial rotating machinery, the Bently Nevada 21000-28-05-15-50-03-02 provides secure mechanical containment and environmental sealing for proximity transducers. This heavy-duty aluminum housing assembly facilitates precise probe positioning and adjustment while maintaining external structural integrity against harsh atmospheric contaminants, oil, and moisture. Engineered as part of critical machinery protection and turbine supervisory instrumentation (TSI) installations, it ensures optimal alignment of the probe relative to the target shaft without requiring the system to be fully depressurized during routine maintenance or adjustment cycles.
| Parameter | Specification Value |
|---|---|
| Manufacturer | Bently Nevada (Baker Hughes) |
| Model Number | 21000-28-05-15-50-03-02 |
| Housing Material | Cast Aluminum |
| Probe Thread Option (-28) | 3/8-24 UNF Thread |
| Conduit Thread Option (-05) | 1/2-14 NPT (Single Conduit Entry) |
| Hazardous Area Approval (-15) | ATEX / IECEx / North American Multi-Approvals |
| Sleeve Length Option (-50) | 5.0 Inches (127 mm) Sleeve Length |
| Fluid Seal Option (-03) | Fluid Seal Option Included (Coaxial Connection Protector) |
| Operating Temperature Range | -40 degC to +100 degC |
| Ingress Protection Rating | IP66 / NEMA 4X equivalent |
| Country of Origin | United States (USA) |
| Shipping Weight (Calculated) | 2.2 kg (4.8 lbs) |
| Package Dimensions (Calculated) | 300 mm x 150 mm x 150 mm |
The Bently Nevada 21000 series aluminum housing is compatible with industry-standard 3300 XL 8mm and 5mm proximity probes. If your installation is located in a highly corrosive marine environment or exposed to continuous acidic washdowns, consider upgrading to the 31000 series housing, which substitutes the cast aluminum body with 316 stainless steel to eliminate galvanic oxidation risks.
When deploying the 21000-28-05-15-50-03-02 on high-temperature steam turbine casings, mechanical engineers must account for thermal expansion of both the machine casing and the 5.0-inch housing sleeve. Operating temperatures above 85 degC can introduce measurable physical expansion in the housing, which directly alters the calibrated sensor gap. Perform dynamic verification tests once the machinery reaches thermal equilibrium.
Ensure that high-temperature thread-locking compound is applied only to the mounting flange adapters and not to the proximity probe's primary adjustment threads. When securing the 1/2-14 NPT conduit connection, use a certified industrial thread sealant (such as PTFE paste or high-grade anti-seize) to guarantee physical compliance with IP66 moisture intrusion ratings and safe explosive atmosphere containment.
Prior to starting any installation, calibration, or maintenance procedure on the housing assembly, verify that the machinery is completely de-energized, locked out, and tagged out (LOTO). Ensure that any localized process pressure within the machine casing has been fully bled and verified at zero atmospheric delta to prevent catastrophic ejection of the probe sleeve during adjustment.
Ensure the mounting surface on the machine casing is clean, completely flat, and free of burrs or remnants of old gaskets.
Thread the proximity probe into the internal 3/8-24 UNF threaded sleeve, making sure the probe cable does not twist or bind.
Calibrate the mechanical gap of the probe using a calibrated digital voltmeter linked to the proximity proximitor sensor output.
Securely tighten the housing sleeve locknut to prevent drift caused by ambient machine vibration, and attach the external conduit line.
Global Express Shipping
Returns & Warranty
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| Country of origin |
United States
|