The CE620 444‑620‑000‑211‑A2‑B100‑C72‑L05 is a premium, Ex‑certified piezoelectric accelerometer with integrated electronics from Meggitt’s renowned vibro‑meter® product line, specifically engineered for general‑purpose vibration monitoring in potentially explosive atmospheres where intrinsic safety is required and a rugged, sealed cable assembly is essential for reliable signal transmission. This Ex‑certified version features a sensitivity of 100 mV/g and is supplied with a factory‑fitted integral cable of 5 metres in length, protected by a stainless‑steel overbraid, terminated with flying leads for direct wiring. This ready‑to‑install configuration eliminates the need for a separate connector at the sensor end, providing a continuous, hermetically sealed connection that is ideal for permanent installations in hazardous areas where long‑term signal integrity, protection against environmental ingress, and mechanical durability are critical. The sensor delivers a voltage output signal proportional to acceleration, with an extended frequency response from 0.5 Hz to 14 kHz, making it suitable for a wide array of rotating and reciprocating machinery in oil refineries, chemical plants, gas terminals, offshore platforms, and mining operations where explosive gas, dust, or firedamp may be present.
The CE620 444‑620‑000‑211‑A2‑B100‑C72‑L05 is an industry‑standard IEPE (Integrated Electronics Piezo Electric) sensor that requires a constant current power supply (2 to 10 mA) and operates from a 22 to 28 VDC supply. It provides a low‑impedance voltage output with a nominal bias voltage of 12 VDC, which carries the AC vibration signal superimposed on the DC level. The integrated electronics incorporate an internal shield and are galvanically isolated from the sensor case, ensuring exceptional noise immunity, reduced ground‑loop interference, and stable bias‑voltage performance even in electrically noisy industrial environments. For Ex ia installations, the sensor must be connected through an approved intrinsically safe barrier or galvanic isolation unit that limits the voltage, current, and energy to levels that cannot ignite the explosive atmosphere, in accordance with the parameters specified in the Ex certificates.
The sensor is housed in a hermetically sealed stainless‑steel case (AISI 316L) with an IP68 protection rating, offering full protection against dust, prolonged water immersion, and a wide range of industrial contaminants. The integral cable is a Teflon® FEP twisted‑pair shielded cable with a stainless‑steel (AISI 316L) overbraid, providing excellent mechanical protection against abrasion, cutting, and chemical attack. The cable is terminated with flying leads (red for positive, white for common), allowing direct connection to the monitoring system or junction box without the need for an intermediate connector. This simplifies installation, reduces potential failure points, and ensures a sealed, leak‑tight assembly from the sensor to the flying leads. The maximum cable temperature rating is 200 °C, exceeding the sensor’s operating range, ensuring compatibility with high‑temperature environments.
With an extended frequency response of ±5 % from 0.5 Hz to 14 kHz, a nominal resonant frequency of 40 kHz, and a dynamic range of ±80 g, the CE620 444‑620‑000‑211‑A2‑B100‑C72‑L05 captures low‑frequency structural vibrations and high‑frequency gearmesh signatures with equal fidelity. Its temperature range of –55 °C to 120 °C, combined with excellent temperature stability, ensures reliable operation in both cryogenic and high‑temperature process environments. The sensor carries ATEX (LCIE 20 ATEX 3039 X) and IECEx (IECEx LCIE 20.0026X) certifications for Ex ia IIC T4 Ga (gas zones 0, 1, 2), Ex ia IIIC T135°C Da (dust zones 20, 21, 22), and Ex I M1 for mining applications (firedamp). EA3C Russian Federation certification is also available. This makes the CE620 444‑620‑000‑211‑A2‑B100‑C72‑L05 one of the most versatile Ex‑certified accelerometers for global deployment in hazardous areas, with the added benefit of a factory‑sealed integral cable for maximum reliability.
This product introduction provides a comprehensive description of the CE620 444‑620‑000‑211‑A2‑B100‑C72‑L05, including key features, applications, detailed technical specifications in tabular form, installation guidelines, ordering information, and available accessories. All information is derived from the official Meggitt data sheet (CE620, 2022) and reflects the company’s commitment to engineering excellence and safety in extreme environments.
Key Features and Benefits
Ex Certified for Hazardous Areas – The CE620 444‑620‑000‑211‑A2‑B100‑C72‑L05 is approved for use in potentially explosive atmospheres with ATEX (LCIE 20 ATEX 3039 X) and IECEx (IECEx LCIE 20.0026X) certifications for Ex ia IIC T4 Ga (gas zones 0, 1, 2), Ex ia IIIC T135°C Da (dust zones 20, 21, 22), and Ex I M1 (mining – firedamp). EA3C Russian Federation certification is also available. This ensures global compliance for installation in the most severe hazardous areas, including Zone 0 and Zone 20.
Integral Cable with Stainless‑Steel Overbraid – 5 Metre Length – The factory‑fitted 5‑metre cable (Teflon® FEP, twisted‑pair shielded) with a stainless‑steel (AISI 316L) overbraid provides exceptional mechanical protection, chemical resistance, and durability. The sealed, connector‑less design eliminates potential failure points at the sensor interface, ensuring long‑term signal integrity in harsh environments. The 5‑metre length is ideal for many installations where the sensor is mounted close to the monitoring electronics but still requires a rugged cable.
High Sensitivity and Wide Dynamic Range – With a sensitivity of 100 mV/g ±5 % and a dynamic range of ±80 g, the sensor captures a broad spectrum of vibration amplitudes, from subtle bearing wear to severe imbalance events, without saturation.
Extended Frequency Response – The sensor offers a flat frequency response of ±5 % from 0.5 Hz to 14 kHz, covering very low‑frequency structural motions and high‑frequency gearmesh and blade‑pass frequencies. The –3 dB point at the low end extends even lower, enabling measurement of ultra‑slow machinery.
Low Noise and High Resolution – The residual electrical noise is exceptionally low, with spectral density as low as 5 μg/√Hz at 100 Hz and above, ensuring clear detection of low‑level vibrations. The internal shielding and isolated electronics further suppress electromagnetic interference, which is particularly important in industrial environments with strong electrical fields.
Integrated Electronics (IEPE) – The built‑in charge‑to‑voltage converter eliminates the need for an external charge amplifier. The 2‑wire interface carries both power and signal, simplifying cabling and reducing system cost. The sensor operates with a constant current of 2 to 10 mA and a supply voltage of 22 to 28 VDC.
Ground‑Isolated Case with Internal Shield – The sensor case is electrically isolated from the signal ground, with a minimum isolation resistance of 100 MΩ, preventing ground loops. An internal shield further enhances noise rejection, ensuring clean signal transmission even when mounted on grounded metal structures.
Rugged IP68 Stainless‑Steel Construction – The hermetically sealed AISI 316L stainless‑steel housing provides IP68 protection, making the sensor impervious to dust, water immersion, and corrosion. This ensures long‑term reliability in the harshest industrial environments, including offshore, chemical, and outdoor installations.
Wide Operating Temperature Range – The CE620 444‑620‑000‑211‑A2‑B100‑C72‑L05 operates continuously from –55 °C to 120 °C, with a temperature sensitivity deviation of –10 % at –55 °C and +5 % at 120 °C, referenced to 20 °C. This makes it suitable for applications ranging from cryogenic pumps to hot turbine casings in hazardous areas.
High Shock and Vibration Tolerance – With a continuous vibration limit of 500 g peak and a shock limit of 5000 g peak, the sensor withstands severe mechanical transients without damage, ensuring survivability in demanding machinery environments.
Low Base Strain Sensitivity – The base strain sensitivity is only 0.0002 g peak/με, minimising measurement errors caused by mounting surface deformation, a common issue in thin‑walled structures.
Factory Sealed Assembly – The integral cable is factory‑welded to the sensor, ensuring a leak‑tight, hermetically sealed assembly that prevents moisture ingress and guarantees long‑term reliability. The cable’s stainless‑steel overbraid provides additional mechanical protection against abrasion and cutting.
Easy Installation – The flying leads (red/white) allow direct connection to terminal blocks or junction boxes, eliminating the need for a separate connector and simplifying wiring. The sensor is supplied with adapter studs (1/4″‑28UNF and M8×1.25) for versatile mounting.
Factory Calibration – Each unit is dynamically calibrated at the factory; no subsequent calibration is required under normal use, reducing maintenance costs.
CE Marked and RoHS Compliant – The sensor meets European Union EMC (2014/30/EU) and RoHS (2011/65/EU) requirements, ensuring global acceptance.
Applications
The CE620 444‑620‑000‑211‑A2‑B100‑C72‑L05 is ideally suited for general‑purpose vibration monitoring in hazardous areas (gas, dust, and mining) where intrinsic safety is required and a robust integral cable is preferred, including:
Oil and Gas Industry – Monitoring of compressors, pumps, turbines, and reciprocating machinery in refineries, gas processing plants, and offshore platforms where flammable gases (IIC group) are present, and the integral cable provides a sealed, maintenance‑free connection.
Chemical and Petrochemical Plants – Surveillance of reactors, mixers, centrifuges, and fans in Zone 0, 1, and 2 classified areas where explosive vapours or dusts may occur, with the sensor cable routed to a safe junction box.
Pharmaceutical and Food Processing – Vibration monitoring in solvent‑handling areas and dust‑explosive environments (e.g., sugar, flour, starch) where intrinsic safety is mandatory and a sealed cable prevents contamination ingress.
Mining – Monitoring of crushers, mills, conveyors, and ventilation fans in coal mines and other extractive industries where firedamp (methane) may be present (Ex I M1 certification), with the integral cable protected by its stainless‑steel overbraid against abrasion.
Power Generation – Vibration measurement on gas turbines, generators, and auxiliary equipment in co‑generation and thermal power plants with potential explosive atmospheres, where the sensor is mounted on the turbine and the cable routed to the control panel.
Marine and Offshore – Propulsion systems, deck machinery, and cargo pumps on tankers and FPSO vessels operating in hazardous zone classifications, where the sealed cable assembly withstands salt‑spray and humidity.
Wastewater and Biogas – Monitoring of pumps, blowers, and mixers in biogas plants and wastewater treatment facilities where methane or hydrogen sulphide may be present, with the cable protected by its overbraid against mechanical damage.
Hazardous Area Test and Measurement – Permanent installations for performance validation and predictive maintenance in Ex‑classified zones, where the integral cable simplifies installation and reduces potential leak paths.
Detailed Description of the Ex Integral Cable Version (444‑620‑000‑211‑A2‑B100‑C72‑L05)
The CE620 444‑620‑000‑211‑A2‑B100‑C72‑L05 is the Ex‑certified, integral‑cable variant of the CE620 family, featuring a sensitivity of 100 mV/g, a temperature range of –55 °C to 120 °C (option A2), and a factory‑fitted 5‑metre cable with stainless‑steel overbraid. It is designed for permanent installation in hazardous areas where intrinsic safety (Ex ia) is required and where a robust, sealed, connector‑less solution is needed to maximise reliability and minimise installation complexity. The sensor is built around a piezoelectric sensing element that generates an electrical charge proportional to acceleration. The integrated electronics package, housed within the sensor casing, converts this charge into a low‑impedance voltage signal, which is transmitted over the integral cable.
The sensor’s output is a voltage signal consisting of a DC bias voltage (nominal 12 V) and an AC vibration component superimposed on it. The bias voltage provides a reference level and also powers the internal electronics. The sensor requires an external constant current power supply (IEPE conditioner) that provides a current source between 2 and 10 mA (typically 4 mA) and a DC voltage of 22 to 28 V. The current source is connected in series with the signal line, and the AC vibration signal is measured across a load resistor in the monitoring system, typically extracting the AC component via a high‑pass filter. The low‑frequency cutoff is determined by the time constant of the coupling capacitor and load resistor; the sensor itself has a –3 dB point at 0.5 Hz, making it suitable for very low‑frequency measurements.
For Ex ia installations, the sensor must be connected through an approved intrinsically safe barrier or galvanic isolation unit that limits the voltage, current, and energy to levels that cannot ignite the explosive atmosphere. The barrier must comply with the parameters specified in the Ex certificate (LCIE 20 ATEX 3039 X and IECEx LCIE 20.0026X). The sensor itself is designed with internal protection to ensure that under fault conditions, the energy remains below ignition thresholds. The intrinsic safety parameters (e.g., maximum voltage Ui, current Ii, power Pi, capacitance Ci, inductance Li) are provided in the certificate and must be respected when designing the loop.
The ground‑isolated design, with an internal shield, ensures that the sensor case and mounting base are electrically isolated from the signal ground with a minimum isolation resistance of 100 MΩ. This is critical in industrial settings where multiple earth points can create ground loops, leading to measurement errors and noise. The internal shield further attenuates electromagnetic interference, ensuring clean signal transmission even in environments with strong electrical fields.
The mechanical construction features a hermetically welded stainless‑steel housing (AISI 316L) that provides IP68 protection against dust and prolonged water immersion. The integral cable is welded to the sensor at the factory, creating a continuous, leak‑tight seal that prevents moisture ingress and ensures long‑term reliability. The cable is a Teflon® FEP twisted‑pair shielded cable with 2×0.5 mm² conductors, providing excellent electrical insulation and low capacitance. The stainless‑steel overbraid (AISI 316L) offers robust protection against abrasion, cutting, and chemical attack, making the cable suitable for routing through cable trays, conduits, or exposed to harsh environments. The cable is terminated with flying leads (red for positive, white for common), allowing direct wiring to terminal blocks or junction boxes, eliminating the need for an intermediate connector that could be a potential failure point. The 5‑metre length is a practical choice for many applications, providing sufficient reach from the sensor to a nearby junction box or control panel without excessive cable handling.
The mounting interface is a 1/4″‑28 UNF‑2A external thread, and the sensor is supplied with two adapter studs: one 1/4″‑28UNF to 1/4″‑28UNF and one 1/4″‑28UNF to M8×1.25. These allow direct mounting onto common machine threads. The recommended mounting torque for the stud is 2.4 N·m (1.8 lb‑ft), ensuring proper coupling and optimal high‑frequency response.
The CE620 444‑620‑000‑211‑A2‑B100‑C72‑L05 is factory‑calibrated at a reference frequency and amplitude, with the sensitivity verified to be within ±5 % of the nominal 100 mV/g. The calibration is performed using a known acceleration standard, and no further calibration is required during the sensor’s lifetime under normal operating conditions. However, periodic verification (e.g., every 2‑5 years) is recommended for critical safety‑related applications.
This integral‑cable version is particularly advantageous for Ex installations where a connector at the sensor end is undesirable due to space constraints, vibration, or environmental sealing requirements. The factory‑sealed assembly ensures that the connection between sensor and cable is as reliable as the sensor itself, reducing maintenance and increasing system uptime. The 5‑metre length is sufficient for most machinery monitoring applications where the sensor is mounted on the machine and the cable runs to a nearby junction box or directly to the monitoring system.
The Ex certification covers gas groups IIC (including hydrogen, acetylene) and IIIC (conductive dusts), as well as mining applications (Ex I M1 for firedamp). The temperature class T4 (135 °C) ensures that the sensor surface temperature does not exceed 135 °C under normal or fault conditions, making it suitable for atmospheres with ignition temperatures above 135 °C. The sensor is therefore suitable for the most severe hazardous area classifications, including Zone 0 (continuous explosive gas atmosphere) and Zone 20 (continuous explosive dust atmosphere).
Installation and Mounting Guidelines
Proper installation is essential to achieve the specified performance and maintain the Ex certification of the CE620 444‑620‑000‑211‑A2‑B100‑C72‑L05. The following guidelines are based on Meggitt’s recommended practices and the requirements of the applicable Ex certificates:
Mounting Surface Preparation – The mounting surface should be flat, smooth, and clean. Any burrs, paint, or corrosion must be removed to ensure full contact between the sensor base (or adapter stud) and the machine surface. A surface finish of 1.6 µm (63 µin) or better is recommended for optimal high‑frequency response.
Adapter Stud Selection – The sensor is supplied with two adapter studs: one 1/4″‑28UNF (straight) and one M8×1.25. Choose the stud that matches the threaded hole in the machine or the mounting block. If a different thread is required (e.g., M6), optional mounting adaptors (MA122_012 or MA122_021) are available.
Torque Application – Screw the chosen stud into the sensor base (using the 1/4″‑28 UNF‑2A thread) and tighten to the recommended torque of 2.4 N·m (1.8 lb‑ft). Then mount the assembled sensor onto the machine surface, applying the appropriate torque for the machine thread (e.g., 15‑20 N·m for M8, but refer to the machine manufacturer’s recommendations). Do not over‑torque, as this may damage the threads or the sensor housing.
Orientation and Alignment – The sensor is sensitive along its principal axis (marked on the housing). Align the sensor such that the principal axis coincides with the direction of the vibration to be measured (axial, radial, or tangential). Refer to the installation manual for detailed orientation diagrams.
Cable Routing and Termination – Ex Requirements – The integral cable has a stainless‑steel overbraid. Route the cable with a minimum bend radius to avoid stress and internal damage (recommended > 25 mm). Secure the cable at intervals using P‑clips or cable ties, but avoid over‑tightening that could deform the overbraid. All cable glands and junction boxes in the hazardous area must be Ex‑certified and installed according to local regulations. The flying leads (red and white) should be connected to the monitoring system’s constant current supply and signal input, preferably through a certified junction box. Connect red to the positive supply/signal line, and white to the return/common. The cable shield should be grounded at one end (typically at the monitoring system) to minimise electromagnetic interference.
Electrical Connections – Intrinsic Safety – The sensor must be connected through an approved intrinsically safe barrier or galvanic isolation unit (e.g., GSI127) that limits the voltage, current, and power to the values specified in the Ex certificate (LCIE 20 ATEX 3039 X / IECEx LCIE 20.0026X). The barrier must be located in the safe area or be certified for installation in the hazardous area. The supply voltage must be within 22 to 28 VDC, and the current must be between 2 and 10 mA. The signal is measured as the AC voltage on the bias level (typically 12 V) via a decoupling capacitor in the monitoring system. Ensure the monitoring system provides the appropriate high‑pass filtering (usually with a cutoff frequency at or below 0.5 Hz). The cable capacitance and inductance must be within the permissible limits to avoid spark ignition. Refer to the certificate for specific parameters (Ui, Ii, Pi, Ci, Li) and special conditions for safe use.
Grounding – The sensor’s base is isolated from the signal ground, so the mounting surface can be at any potential without affecting the signal. However, the cable shield should be grounded at one end (usually at the monitoring system) to minimise electromagnetic interference. Follow the grounding practices recommended in the system’s installation manual and the Ex certificate requirements.
Thermal Considerations – The sensor is rated for continuous operation up to 120 °C, which ensures the surface temperature does not exceed the T4 rating (135 °C) even under fault conditions. The cable is rated up to 200 °C, exceeding the sensor’s limit. If the mounting surface exceeds 120 °C, use a thermal insulating adaptor (e.g., MA122_021) or mount the sensor remotely with an extension rod. Ensure that the cable is not routed over hot surfaces that exceed its 200 °C rating.
Protection from Physical Damage – In harsh environments, protect the cable from impacts, abrasion, and chemical attack. The stainless‑steel overbraid provides substantial protection, but additional conduits or protective covers may be required in extreme conditions. The IP68 rating ensures the sensor is dust‑tight and protected against water immersion, but mechanical protection is still recommended.
Hazardous Area Precautions – Installation must be carried out by competent personnel trained in Ex practices. All wiring, cable glands, and junction boxes must comply with local regulations and the relevant Ex standards. The sensor and its associated cables must be protected from mechanical damage and chemical attack. Regular inspection and maintenance as per the plant’s safety procedures are mandatory. The Ex certificate includes special conditions for safe use (e.g., the sensor must be used with a certified barrier, and the cable must be secured to avoid strain).
Commissioning – Before energising, verify that all connections are correct, the Ex barrier is properly installed, and the cable routing does not subject the connector to excessive strain. Perform a functional test using a known vibration source to confirm sensitivity and bias voltage. Record the bias voltage and signal levels for future reference.
Commissioning and Verification
After installation, the CE620 444‑620‑000‑211‑A2‑B100‑C72‑L05 should be verified using a known vibration source (e.g., a portable shaker or a reference accelerometer) or by comparing with a known good sensor. The bias voltage should be measured to confirm it is approximately 12 V (within ±1 V). The AC signal should be checked for proper sensitivity; a known acceleration level (e.g., 1 g at 80 Hz) should produce the expected output (100 mV/g). Also verify that the signal is free from excessive noise and that the low‑frequency cutoff is appropriate for the intended measurement. In Ex installations, verify that the barrier is operating within its specified parameters. For long‑term monitoring, regular system checks during routine maintenance are recommended.
Accessories
A range of accessories is available to complement the CE620 444‑620‑000‑211‑A2‑B100‑C72‑L05, including additional adaptor studs and mounting adaptors. The sensor is supplied with two adaptor studs; optional items are listed below. For Ex installations, ensure that any additional accessories used in the hazardous area are suitably certified.
ITEM | TYPE | DESCRIPTION | PART NUMBER (PNR) |
Supplied Adaptor Studs | – | 1/4″‑28UNF (to 1/4″‑28UNF) and M8×1.25 (to 1/4″‑28UNF) | 809‑601‑000‑011 and 809‑601‑000‑021 |
Optional Adaptor Stud | – | 1/4″‑28UNF‑2A to M8×1 | 809‑601‑000‑031 |
Mounting Adaptors | MA122_012 | 1/4″‑28UNF‑2A to M6, with conic base | 809‑122‑000‑012 |
| MA122_021 | 1/4″‑28UNF‑2A to M6, with conic base (insulating stud) | 809‑122‑000‑021 |
Galvanic Separation Units | GSI127 | Provides galvanic isolation and intrinsic safety barrier for Ex ia installations; must be used with this sensor in hazardous areas | Refer to separate data sheet |
Cable Protection (if needed) | – | Additional conduits or flexible hoses can be used to further protect the integral cable; consult Meggitt for recommendations. | N/A |
Note: As this is an integral cable version, separate cable assemblies are not required. However, if an extension is needed, a junction box can be used to connect the flying leads to a longer cable run, ensuring that the total cable capacitance and inductance remain within the limits specified by the Ex certificate and the barrier.
Disposal and Environmental Compliance
At the end of its service life, the CE620 444‑620‑000‑211‑A2‑B100‑C72‑L05 must be disposed of in accordance with local environmental regulations. The sensor contains stainless steel, electronic components, and piezoelectric materials; the cable contains fluoropolymer insulation and metal conductors. In the European Union, the Waste Electrical and Electronic Equipment (WEEE) Directive applies – separate collection and recycling are mandatory. Meggitt supports environmentally responsible disposal and can provide guidance on proper recycling channels.
