Isolated Data Acquisition
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Ground loop elimination – Signal isolation – Noise protection
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 Isolated Analog Inputs and Outputs  Isolated Analog Inputs  Isolated Analog Outputs  Isolated Analog Outputs  Isolated Digital Inputs and Outputs |
As the accuracy of your signals goes up, you need to protect against noise. In harsh environments, you need to protect against accidental overvoltages. A harsh environment is a clear threat, but noise is more subtle, persistent, and pervasive.
- Noise generated by a PC distorts a signal.
- So does noise from ground loops.
In every case, you need to protect your signal on the path from its source up to the point of data conversion. You have a range of products to choose from to achieve this. Make your choices based on how much protection you want.
Solution
The solutions take the form of MSXB boards in Eurocard B format. The boards occupy slots in standard 19-inch industrial enclosures. Each enclosure has its own power supply and factory-installed digital backplane. The entire package shares a ground with the PC. The individual MSXB boards are isolated from the PC, however.
A Data Acquisition Processor (DAP) board sends signals to and receives signals from the backplane. A single DAP board can communicate with up to eight of the MSXB input boards, and with a larger number of them when they are configured for output. Several DAP boards can form a networked system with hundreds of synchronized channels of isolated inputs and outputs on MSXB boards.
Isolation
Only digital signals cross the isolation barrier on each MSXB board, with the exception of the MSXB 027. Analog to digital converters and digital to analog converters are on the system side of the isolation barrier. See diagram above. Each MSXB board is isolated from every other board. 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 Connection
All signals are connected to MSXB boards outside – and isolated from – the PC. The boards 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 Output
The MSXB 076 analog output board and MSXB 075 analog output board 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 board. The MSXB 075 has four channels of isolated analog output per board.
Digital Input and Digital Output
The MSXB 078 digital input and output board provides sixteen input channels and sixteen output channels. Both the input and the output sections are isolated from the PC.
Analog Input
The MSXB 084 analog input board provides sixteen differential analog input channels isolated from the PC.
Analog Input and Analog Output
The MSXB 085 analog input and output board provides sixteen input channels and two output channels. Both the input and the output sections are isolated from the PC.
Custom Models
All the above MSXB products are FPGA-based for flexibility. Parameters are stored in onboard flash memory. OEMs, VARs and others with volume requirements are welcome to call to discuss custom models to suit their end-user systems.
Channel-to-PC Isolation
MSXB 085: Isolated Analog Input and Output Expansion Boards
MSXB 084: Isolated Analog Input Expansion Boards
MSXB 078: Isolated Digital Expansion Boards
See also: specialized DAP board iDSC 1816
Channel-to-Channel Isolation
MSXB 076: Isolated 16-Bit Analog Output Expansion Boards, Eight Channels per Board
MSXB 075: Isolated 16-Bit Analog Output Expansion Boards, Four Channels per Board
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 board 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 boards that work with it?
