SCXI-1120D input voltage protection:

Hello All,
I have a SCXI-1120D input voltage protection question:
the data sheet specified 250Vrms. Does it mean signal plus CMV only? What if my signal itself is has a large potential difference (thus not CMV) , say 20V? Will the SCXI 1120D be damaged?
Thanks
Feilong

Hi Feilong,
You are correct. The 250 Vrms refers to your signal plus the CMV. See Figure 3-2 on page 32 of the SCXI 1120D User Manual. The paragraph above Figure 3-2 also explains this. I hope this helps!
Regards,
Ima
Applications Engineer
National Instruments
LabVIEW Introduction Course - Six Hours
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SCXI-1120D input voltage protection:

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