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Q.series X: Ethernet, CAN, ProfiNet Interface


Introduction to Localbus

Localbus is Gantner Instruments’ proprietary communication protocol that connects directly, the CPU to one or more slots of the expansion bus. This method avoids bottlenecking created by the expansion bus, creating a much faster throughput. The LocalBus (RS485) between a Gantner Instruments Q.station X controller and I/O modules can achieve speeds up to 48 Mbps.

The Q.series X product line is compatible with all industry-standard fieldbuses and communication protocols. For applications requiring Ethernet, CAN, and ProfiNet Fieldbus connectivity, the specific Q.series X products best fit for these applications are designated Q.series XL.

Dive deeper into Localbus with our knowledge base:

Interface for Transmitting High Volumes of Data

Q.series XL modules are connected to the Q.station X controller via serial RS-485 interfaces with very high data rates. Despite the potential for distributed set-ups, measurement is in sync with a maximum jitter of 1μs. The Q.station X controller provides different interfaces for PCs and automation systems depending on the controller type.

For more information on the Q.station X Controller:

Peer-to-Peer Communication between Modules

The Q.series XL measurement modules communicate through a 48 MBaud serial bus (Localbus) serial. Their variables are written into time slots, which in turn may be read by any other module. Thereby, each module can access the variables of the other modules to display them, for example. This method reduces loading times and computational load since the data does not need to run through a controller.

Signal Conditioning Decentralized, Fast, and Accurate

Q.series XL measurement modules provide a sampling rate of up to 100 kHz per channel. The signal conditioning for data reduction is also processed at this rate, such as filtering with high-, and low-and band-pass characteristics, storing minimums or maximums, and calculating the RMS value. This means that the high dynamic signals are already reduced to their signal components at the beginning of the conditioning chain, thus avoiding information overload. More conditioning algorithms are available.

Sigma Delta or Successive Approximation

Q.series XL measurement modules digitize the analog measurement signals with a 24-bit sigma-delta converter guaranteeing maximum stability and noise rejection. To minimize runtimes for closed systems applications such as control tasks, the Q.series XL module A102 offers analog output, and measurement signals are digitized using 19 bit / 100 kHz in successive approximation.

Understanding Q.series XL

All Q.series X DAQ systems possess the same measurement capabilities and performance. The main differentiating factor between the XL and XE versions of Q.series X is the Fieldbus communication protocol, which can be interchanged on Q.series X modules using a simple firmware update.

Q.series XL DAQ systems are specialized for Localbus (XL) Fieldbus communication and possess interfaces for CAN, Modbus TCP/IP, Modbus RTU, PROFIBUS, PROFINET, publish/subscribe and messaging protocols, e.g., OPC UA, DDS, and MQTT and custom controller plugins for customer-specific communication protocols.

Advantages of Q.series XL Controllers

The Q.station X Controller and Q.series XL measurement modules are designed for industrial and experimental testing. Q.series XL products are exceptionally well suited for performing highly synchronized, multi-channel measurements of electrical, mechanical, and thermal signals on engine and component test benches and long-term process monitoring applications. 

Q.series XL modules are combined together to form custom DAQ systems as needed. Connect up to 64 Q.series XL measurement modules to a single Q.station X Test Controller. For all measurement modules, the power supply, bus interface, and I/O (analog and digital) are all electrically isolated from each other.

Why use Localbus

  • Up to 100 kHz S/s
  • Faster speed of data transfer
  • Larger module capacity than EtherCAT
  • Powerful controller capabilities
  • Edge computing and PC-less control (i.e., test.con)
  • 24/7 PC-less operation and logging

If you need EtherCAT connectivity, then Q.series XE products may be the best fit for you.

Your guide to Q.series XL products

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