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.
Engineered specifically for low-frequency vibration monitoring on cooling tower fans and slow-speed machinery, the Bently Nevada 190501-12-99-02 Velomitor CT utilizes an internal solid-state accelerometer and integration circuitry to provide a direct velocity output. This specialized sensor is designed to detect early-stage mechanical anomalies in harsh, high-humidity environments, facilitating proactive maintenance before operational failures occur.
By integrating the velocity transduction mechanism directly within the rugged housing, this unit eliminates the signal degradation issues commonly associated with external charge amplifiers. The configuration features a 32-foot integrated cable and a robust M8x1 plate stud mount, providing a ready-to-install solution optimized for wet, demanding industrial structures.
| Manufacturer | Bently Nevada |
| Model Series | 190501 Velomitor CT (Cooling Tower) |
| Full Part Number | 190501-12-99-02 |
| Mounting Option (-12) | Plate Stud 3/8-in 24 to M8x1 |
| Connection Option (-99) | Integrated 32-foot (9.7m) cable |
| Agency Approval Option (-02) | Multiple approvals (ATEX, IECEx, Division 2 / Zone 2 compliant) |
| Shipping Weight (Calculated) | 2.0 kg (4.4 lbs) |
| Wire Color | Signal Assignment | Description |
|---|---|---|
| White | SIG / PWR (+) | Positive dynamic signal and loop power input |
| Black | RET (-) | Signal return / common ground reference |
| Shield | SHIELD | Drain wire connected to shield; terminate at monitor chassis ground |
The Velomitor CT (190501) features a lower frequency filter profile optimized for low-velocity cooling tower machinery compared to the standard Velomitor (330500). Do not substitute a standard 330500 sensor on a cooling tower fan unless you reconfigure the monitor's low-frequency corner limits in the 3500 rack configuration software, as doing so may cause false alarms or miss critical low-frequency blade-pass energy.
While the integrated 32-foot cable (Option -99) provides a seamless seal against moisture ingress at the sensor head, the free end of the cable is vulnerable. Always route this cable through liquid-tight conduit up to a localized junction box. Ensure the localized junction box uses a breather drain to prevent condensation from wicking down the cable sheath and corrupting the high-impedance signal.
Always ensure the shield drain wire is isolated and cut back at the transducer end. Ground the shield exclusively at the monitoring system's terminal base (e.g., the 3500/42M monitor input card). Grounding the shield at both ends introduces a ground loop that will inject 50/60 Hz line noise into your dynamic vibration plot, distorting diagnostic spectrum analysis.
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Engineered specifically for low-frequency vibration monitoring on cooling tower fans and slow-speed machinery, the Bently Nevada 190501-12-99-02 Velomitor CT utilizes an internal solid-state accelerometer and integration circuitry to provide a direct velocity output. This specialized sensor is designed to detect early-stage mechanical anomalies in harsh, high-humidity environments, facilitating proactive maintenance before operational failures occur.
By integrating the velocity transduction mechanism directly within the rugged housing, this unit eliminates the signal degradation issues commonly associated with external charge amplifiers. The configuration features a 32-foot integrated cable and a robust M8x1 plate stud mount, providing a ready-to-install solution optimized for wet, demanding industrial structures.
| Manufacturer | Bently Nevada |
| Model Series | 190501 Velomitor CT (Cooling Tower) |
| Full Part Number | 190501-12-99-02 |
| Mounting Option (-12) | Plate Stud 3/8-in 24 to M8x1 |
| Connection Option (-99) | Integrated 32-foot (9.7m) cable |
| Agency Approval Option (-02) | Multiple approvals (ATEX, IECEx, Division 2 / Zone 2 compliant) |
| Shipping Weight (Calculated) | 2.0 kg (4.4 lbs) |
| Wire Color | Signal Assignment | Description |
|---|---|---|
| White | SIG / PWR (+) | Positive dynamic signal and loop power input |
| Black | RET (-) | Signal return / common ground reference |
| Shield | SHIELD | Drain wire connected to shield; terminate at monitor chassis ground |
The Velomitor CT (190501) features a lower frequency filter profile optimized for low-velocity cooling tower machinery compared to the standard Velomitor (330500). Do not substitute a standard 330500 sensor on a cooling tower fan unless you reconfigure the monitor's low-frequency corner limits in the 3500 rack configuration software, as doing so may cause false alarms or miss critical low-frequency blade-pass energy.
While the integrated 32-foot cable (Option -99) provides a seamless seal against moisture ingress at the sensor head, the free end of the cable is vulnerable. Always route this cable through liquid-tight conduit up to a localized junction box. Ensure the localized junction box uses a breather drain to prevent condensation from wicking down the cable sheath and corrupting the high-impedance signal.
Always ensure the shield drain wire is isolated and cut back at the transducer end. Ground the shield exclusively at the monitoring system's terminal base (e.g., the 3500/42M monitor input card). Grounding the shield at both ends introduces a ground loop that will inject 50/60 Hz line noise into your dynamic vibration plot, distorting diagnostic spectrum analysis.
Global Express Shipping
Returns & Warranty
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| Country of origin |
United States
|