Any way to add gain to SCC module SCC-SG04?

[john_he]

I'm trying to use an SCC-SG04 module with a pressure transducer but with only 100x gain my full range will only result in 0.5V out of the SCC to my NI-6221 card.  Has anyone else needed more gain, and/or have ideas?  Can the gain be adjusted if I break a module open and change a resistor (and potentially destroy it)?  Any ideas or cost-effective products for amplifying the signal external to the SCC?

Thanks

John

Message Edited by john_he on 12-14-2006 12:08 PM

[Jennifer O]

Hi John,

You can make use of the gain on the DAQ board to get better resolution of your signal.  By specifying the range, the DAQmx driver will automatically apply the largest gain possible to bring the signal up to full range (+/-10V).  For example, if the physical signal is +/5mV, you would specify this as your range.  The driver knows that the gain on the SG module is 100, bringing the signal up to 0.5V.  The gain on the DAQ board will then be set to 10, bringing the signal up to 5V.  (There are 4 ranges for the NI-6221 +/-200mV,+/-1V,+/-5V and +/-10V.  This corresponding gains are 50, 10, 2 and 1).  You can find this information in the M-Series Help or the NI-6221 Specifications.

Hope this helps,

Jennifer O.
Applications Engineer
National Instruments