Isolated Data Acquisition | ||||||||||||
Ground loop elimination – Signal isolation – Noise protection
As the accuracy of your measurements goes up, the need to protect your signals against noise goes up, too. And in harsh environments, you need to protect your equipment against accidental damage caused by ground currents. In every case, you need to protect your signal on its entire path from the sensor to the point of data conversion. A new product family of signal interface (SI) modules provides this protection for you. Signal Interface ModulesSI modules are offered in the Eurocard B format: 100 mm by 220 mm. Each SI module occupies from one to four slots in a full-width or half-width industrial enclosure or in a DAPserver. For small or proof-of-concept systems, stand-alone or single-module enclosures are available. Scalable Modular SystemsDAPservers – and DAPserver-supported enclosures – that contain SI modules are network-ready data acquisition systems that make their data acquisition services available to any PC on the network. They are scalable modular system (SMS) products. You can have any number of them on a network, scaling up your system as your application grows. SI Modules and DAP BoardsAn SI module connects through a backplane and a cable to a Data Acquisition Processor (DAP) board directly controlled by a PC or by a DAPserver. The SI module shares a ground with the DAP board, but the signal interface cells on each SI module are isolated from the the interface to the DAP board. Isolation eliminates ground loops between the measurement system and the signals you want to measure. Microstar Laboratories offers two types of isolation.
FPGA Technology and Custom ModulesEvery SI module is intelligent: it can communicate with – and be configured by – a DAP board that you control from a PC. All of the isolated signal interface modules are FPGA-based for flexibility. Configuration parameters are stored in onboard flash memory. FPGA technology enables rapid customization. OEMs, VARs and others with volume requirements are welcome to call to discuss custom modules to suit their end-user systems. IsolationOnly digital signals cross the isolation barrier on each SI module. Analog to digital converters and digital to analog converters are on the system side of the isolation barrier. See diagram above. Each SI module is isolated from every other module. Inputs are measured relative to system ground. Outputs are referred to system ground. System signals are protected from PC noise and from ground loops through the PC. System signals are protected from ground loops between channels in products with channel-to-channel isolation. Signal ConnectionAll signals are connected to SI modules outside – and isolated from – the PC. The modules occupy slots in industrial enclosures. Front panels provide standard DB-xx signal connectors, onboard Wago connectors can grip bared signal wires, or headers can be used. Custom front panels also are available. Analog OutputThe MSXB 076 analog output module and MSXB 075 analog output module take their signal input from the digital backplane factory-installed in an industrial enclosure. A DAP board supplies signals to the backplane. Data conversion takes place on the system side of the onboard isolation barrier, and each analog output has its own ground, isolated channel by channel. The MSXB 076 has eight channels of isolated analog output per module. The MSXB 075 has four channels of isolated analog output per module. Digital Input and Digital OutputThe MSXB 078 digital input and output module provides sixteen input channels and sixteen output channels. Both the input and the output sections are isolated from the PC. Analog InputThe MSXB 082 analog input module provides four high-speed simultaneous differential analog input channels, each isolated from each other and the PC. The MSXB 080 analog input module provides eight simultaneous differential analog input channels, each isolated from each other and the PC. The MSXB 084 analog input module provides sixteen differential analog input channels isolated from the PC. Current InputThe MSXB 081 current input signal interface module acts as an 8-channel receiver for 4-20 mA current loops. Each input has its own ground, isolated channel by channel. The MSXB 086 current input signal interface module acts as a 16-channel receiver for 4-20 mA current loops. Current OutputThe MSXB 074 current output signal interface module acts as an 8-channel transmitter for 4-20 mA current loops. Each analog output has its own ground, isolated channel by channel. Analog Input and Analog OutputThe MSXB 085 analog input and output module provides sixteen input channels and two output channels. Both the input and the output sections are isolated from the PC. Channel-to-PC IsolationMSXB 085: Isolated Analog Input and Output Signal Interface Modules MSXB 084: Isolated Analog Input Signal Interface Modules MSXB 078: Isolated Digital Signal Interface Modules MSXB 086: Isolated 4-20 mA Input Signal Interface Modules See also: specialized DAP board iDSC 1816 Channel-to-Channel IsolationMSXB 082: Channel-to-Channel Isolated High-Speed Analog Input Signal Interface Modules MSXB 080: Channel-to-Channel Isolated Analog Input Signal Interface Modules MSXB 076: Channel-to-Channel Isolated 16-Bit Analog Output Signal Interface Modules, Eight Channels per Module MSXB 075: Channel-to-Channel Isolated 16-Bit Analog Output Signal Interface Modules, Four Channels per Module MSXB 081: Channel-to-Channel Isolated 4-20 mA Input Signal Interface Modules MSXB 074: Channel-to-Channel Isolated 4-20 mA Output Signal Interface Modules MSXB 039: Digital Opto-Isolator Boards MSXB 027: Analog Isolation Boards Contact us – our engineers will help you specify the parts for your unique application. Do you need a specific function added to your DAP system? Browse the function list. Or use the overview table. Do you know the part number of the signal interface module you need? Browse the part number list. Do you know the DAP board you use – or will use – and only want to see the signal interface modules that work with it? |