vibro-meter® IQS45x signal conditioners – replaced by the IQS900
Fribourg, September 2020
Dear Customer,
We are contacting you further to your past purchase of an IQS45x signal conditioner from Meggitt’s vibro-meter® product line. While we trust that this product has served you well, Meggitt is committed to offering our customers the best possible measurement and monitoring solutions, to help you to get the most from your machinery. This naturally involves updating and replacing items in our product range.
This letter is to inform you about the replacement of the IQS45x signal conditioners by the new IQS900 signal conditioner, so that you may benefit from the improved design characteristics of this new product.
In addition to matching or bettering the outstanding specifications and performance of the IQS45x, the IQS900 includes the following main improvements:
- Suitable for use in safety-related applications:
- SIL 2 “by design” in accordance with the IEC 61508 functional safety standard
- New grounding concept for improved frame-voltage immunity, and improved electromagnetic immunity and emissions in accordance with the EN 61326-1 and EN 61326-3-2 EMC standards
- PLC Cat 1 in accordance with the ISO 13849 safety of machinery standard
- Smaller output impedance for voltage signal transmission over longer distances
- Optional diagnostic circuitry (that is, built-in self-test (BIST)) providing continuous feedback on the health of the measurement chain – sensor, cabling and signal conditioner
- Raw output pin provides a voltage signal corresponding to internal operation that allows the measurement chain/IQS900 to be verified without disconnecting the output
- Test input pin allows a voltage signal to be injected at the input to the IQS900 in order to verify the operation of the IQS900/monitoring system
- Ex certification for hazardous dust environments, in addition to hazardous gas environments
- New DIN-rail mounting adaptor and removable screw-terminal connectors for easier installation.
Please do not hesitate to contact with me, who will help with any further questions you may have.
The IQS900 signal conditioner is designed for operation with vibro-meter TQ proximity sensors, that is, non-contact proximity sensors / measurement chains based on the eddy-current principle.
Note: The IQS900 is compatible with different TQ9xx (and TQ4xx sensors) and replaces all previous versions of the IQS45x signal conditioner (PNR 244-45x-000-xxx).

The IQS900 signal conditioner provides a dynamic output signal – current (−15.5 to −20.5 mA) or voltage (−1.6 V to −17.6 V) – suitable for advanced condition monitoring applications that require spectral analysis, for example, machinery analytics and diagnostics. In comparison, the IQS910 signal conditioner provides a slowly-varying output signal (4 to 20 mA current-loop) suitable for machinery protection and/or basic condition monitoring applications based on cost-effective trending of overall levels.
The IQS900 is a configurable and versatile device that generates, converts and processes (high-frequency modulator/demodulator) signals from a TQ proximity sensor into a current or voltage output signal suitable for transmission to the monitoring system. For example, it is factory-configurable for sensitivity and measurement range (transfer function), system length, and optional diagnostic circuitry (with variants defined by ordering option code).
The IQS900 is designed and built for long-term use, and is available in standard versions and in Ex versions certified for use in potentially explosive atmospheres (hazardous areas). Similarly, it is also available with or without diagnostics: versions with diagnostics automatically and remotely indicate the health/status of the measurement chain so you always know when measurements can be trusted. The diagnostics (SIL 2 “by design”) bring enhanced reliability and significant risk reduction, making the IQS900 suitable for use in safety-related applications (functional safety contexts).
Features
- Signal conditioning for TQ proximity sensors.
- Shaft relative vibration and gap/position measurement for machinery protection and/or advanced condition monitoring.
- Very wide frequency range (DC to 20000 Hz), with configurable sensitivity and measurement range.
- Current output for signal transmission over long distances or voltage output for signal transmission over medium distances.
- Certified for use in potentially explosive atmospheres (hazardous areas).
- Suitable for use in functional safety contexts: SIL 2 in accordance with IEC 61508 and Cat 1 PL c in accordance with ISO 13849.
- Fully compliant with API 670 5th edition.
- “Raw” output and “Test” input signals for in-situ test support.


