QACQ – a measuring and recording device operating in three modes

QACQ is an unique device in terms of its versatility, offered functions and quality of measurements. It works in three modes as:

• a measuring card,
• an autonomous system for monitoring the condition of machines remotely,
• an event-triggered recorder of machine operating parameters and vibration signal.

In the measurement card mode, QACQ transmits time waveforms to the master device via the Ethernet interface or wirelessly via Wi-Fi. The device is powered from a PoE compatible Ethernet switch or from 24VDC power supply.

QACQ is equipped with 9 measurement channels. It has 3 input types:

• analog with a resolution of 24 bits for fast-changing signals (sampling frequency 65 kHz, type: CLPS/IEPE/ICP, 0÷20 V, 0÷20 mA, 4÷20 mA)
• analog with a resolution of 16 bits for slow-changing signals (sampling frequency 1 kHz, type: 0÷2.5 V, 0÷10 V, 0÷20 mA, 4÷20 mA)
• digital for binary signals (sampling frequency 65 kHz, type: 24V)

All device inputs are fully synchronized.

The construction of multi-channel systems is facilitated by the B4QACQ docking station (). 4 devices installed in it can be disconnected and used independently at any time. All measurement channels of the cooperating systems work in a synchronous manner. It enables the analysis of dynamic relations between the individual elements of the monitored object and the examination of the vibration signal in relation to the angular position of the shaft.

The device was designed to operate with piezoelectric accelerometers of CLPS (IEPE/ICP) type. However, the type of analog inputs can be changed by the users. This can be done by using microswitches located inside the housing. In addition to the vibration signal, QACQ can acquire signals coming from static and dynamic process parameter sensors (temperatures, pressures, flows, levels, valve states, etc.).

Cross-linking the information gathered from different sensors is the basis for implementing parametric analyzes of investigated object’s health. Vibration behavior of machines operating in intermittent cycles or under changing conditions can be easily interpreted and better understood.

In the measurement card mode, QACQ works with applications for mobile devices – mVIBE (link) and mVIDIA (link). For PCs we have developed the Datacquire program (link).

In the monitor mode, QACQ processes the signals coming from the connected sensors in real time. It takes into account the real sensitivity of each transducer. Regardless of the type of vibration sensor used, internally calculated diagnostic parameters may relate to vibration displacement, velocity and acceleration. The list of determined quantities includes:

• effective value (RMS),
• peak value (0-p),
• peak-to-peak (p-p) value,
• average value,
• signal envelope level,
• crest factor,
• S_pp i S_max for the shaft displacement orbit, taking into account fixed or variable position of its center

Using a digital rotation speed sensor allows you to additionally synchronize the acquisition process with:

• starting the machine operation,
• increasing or decreasing the rotational speed by a certain value,
• stabilization of the rotational speed

The calculation results are transferred via the Ethernet or WiFi to dedicated applications using ATC MESbus protocol. Integrated Modbus/TCP allows QACQ to be merged with automation systems. It extends its functionality by supervising technical condition of controlled machines.

Each of the calculated parameters is related to 3 alarm thresholds. They can be set according to the international standards or rules learnt from experience. Information about machine operation anomalies is available in the QACQ’s registers and displayed on the LED indicators. Appropriate reaction of the object control system minimizes the risk of possible machine damages resulting from a single failure. The applied solutions allow assessing the technical condition of machines in accordance with the applicable standards. They also help to detect many faults at an early stage, including:

• unbalance and eccentricity,
• misalignment,
• damage to rolling or plain bearings and their casings,
• oil film instability,
• cavitation,
• loose fastening and cracks in machine structural elements,
• damage to toothed wheels and transmission belts,
• damage to turbines and fans,
• electrical damage to engines,
• critical speeds, resonances

Configuration of communication interfaces, measurement triggering modes, types and parameters of determined analyzes and alarm thresholds is easy thanks to the built-in web server.

Parametric analyzes in conjunction with the unique measurement triggering modes that depend on the current operating conditions of the monitored object eliminate false alarms, e.g. when the machine is starting.

QACQ is optionally equipped with an 8 GB data memory. It allows you to record up to 64 seconds of signal time waveforms and all calculated parameters. Data acquisition is performed periodically or when any of the defined alarm thresholds is exceeded. QACQ has the ability to keep in its memory time waveforms up to 4 seconds before the occurrence of a dangerous or an acquisition-triggering event.

The collected results can be sent to the application installed on a smartphone or to the private or public VIDIA.cloud.

According to the idea of ​​industry 4.0, VIDIA Cloud acts as a distributed center for monitoring the technical condition of machines. It offers remote access to measurement devices as well as measurement and analysis results for users and supporting specialists.

The QACQ’s housing made of aluminum alloy used in aviation industry guarantees its durability and resistance to harsh weather conditions. It also provides the device with IP65 resistance class. What’s more, electronic components of the automotive class ensure long time of proper functioning.

The devices can be optionally delivered with a calibration certificate issued by an accredited or notified laboratory. In case of calibration with accelerometers, a certificate is issued for a vibration meter. It is the best confirmation of high quality and guarantees the precision of the obtained results.