Product Overview
The IQS 450 (204-450-000-001) is a high-performance signal conditioner from the Vibro-Meter product line, specifically engineered for non-contacting proximity measurement systems. It serves as the critical link in an eddy current measurement chain, typically paired with a TQ 402 or TQ 412 transducer and an EA 402 extension cable. This unit converts the transducer's impedance changes into a standardized voltage or current signal proportional to the distance between the probe tip and the target shaft. The 204-450-000-001 configuration is widely used in power plants and petrochemical facilities for measuring shaft vibration and axial position in steam and gas turbines.
Technical Configuration
The 204-450-000-001 variant is a specific hardware build that ensures the high reliability required for industrial protective systems.
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Eddy Current Principle: The unit drives the transducer sensing coil with a high-frequency carrier signal and demodulates the resulting signal to provide a linear output.
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Temperature Compensation: Features sophisticated internal circuitry that compensates for thermal variations at the sensor end, maintaining measurement accuracy from $-40^{\circ}C$ to $+180^{\circ}C$ at the transducer.
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Output Flexibility: Supports both voltage and current transmission. The current modulation allows for signal integrity over long distances (up to 1 km when used with a GSI unit).
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Interchangeability: Part of a calibrated system where the IQS 450, transducer, and extension cable are modular and interchangeable without requiring site-specific recalibration, provided the system lengths match.
Technical Specifications
| Parameter |
Specification Details |
| Model / PNR |
IQS 450 / 204-450-000-001 |
| Brand |
Vibro-Meter (Meggitt) |
| Input Signal |
From TQ 402, TQ 412, TQ 422, or TQ 432 |
| Frequency Response |
DC to 20 kHz (-3 dB) |
| Measuring Range |
2 mm or 4 mm (Probe dependent) |
| Supply Voltage |
-18 VDC to -30 VDC |
| Output Range |
-2 to -18 V (Voltage) / 15.5 to 20 mA (Current) |
| Operating Temp |
-35 to $+85^{\circ}C$ |
| Enclosure |
Moulded Aluminium |
Technical FAQs
What is the significance of the "001" suffix in the part number?
The 204-450-000-001 part number typically identifies the specific revision or calibration grouping of the hardware. In the IQS 450 series, these suffixes often distinguish between standard and specialized mounting or output configurations. Always verify your TSL (Total System Length) requirement (e.g., 1m, 5m, or 10m) to ensure compatibility.
Can I use the IQS 450 with a different brand of proximity probe?
No. Proximity systems rely on a specific carrier frequency and impedance matching between the transducer and the conditioner. The IQS 450 is designed exclusively for the Vibro-Meter TQ-series transducers. Using a non-Vibro-Meter probe will result in a "Sensor OK" error and non-linear data.
How do I check the health of the IQS 450 loop?
Measure the Gap Voltage at the output. A value near -10 VDC typically indicates the sensor is at the midpoint of its linear range. If the voltage is 0V or identical to the supply rail (e.g., -24V), the system is indicating a short circuit or an open loop in the sensor cabling.
Engineering & Installation Guide
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System Length Verification: The IQS 450 is calibrated for a specific electrical length. Ensure that the sum of the transducer cable and the EA 402 extension cable exactly matches the system length (TSL) marked on the conditioner label.
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Mounting: The unit is designed for 35 mm DIN-rail mounting. It should be installed in a protected junction box (such as a JB 118) as close to the machine as practical while remaining within the specified temperature limits.
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Shielding: To prevent EMI from polluting the vibration signal, terminate the cable shields at the IQS 450 end. Ensure the aluminum housing is securely clipped to the DIN rail, which should be connected to a clean instrument ground.
Engineering Advantages
The IQS 450 (204-450-000-001) is distinguished by its Exceptional Linearity. In critical machinery protection, precision is paramount for identifying early signs of shaft instability. The IQS 450 provides a clean, high-bandwidth signal that allows the VM600 system to extract sub-harmonic vibration data and perform advanced diagnostics like shaft centerline plots. Its rugged Swiss design ensures a stable "Zero Point" over years of operation, minimizing the risk of drift-induced false trips.