PXI-6259 2 KHz signal acquire, sound

[reynaj671224]

Hello:

I working with a brakin product ABS motor, with a PWM at 2.8 KHZ, my setup:

-PXI-1042Q Chassis

-PXI-6259 Analog acquisition card.

when I fire the motor in order to measure the peak current and the motor stable current, a sound coming from the PXI chassis like if the Analog card reproduce the 2.8KHZ signal in sound, if i reduce the frequency from the product to 2KHz the sound is loud,

my question is is a NI application engineer can tell me if this is normal or if I violating a card o chassis parameter, the voltage that I reading at peak  1.1 VDC  aprox, and 0.1 and state stable,

attached you can find a complete data coming from the product to the analog card.

the results are good just is bother me the sound,

thanks in advance

Javier Reyna 

[Puchkov]

The frequency and voltage range that you are using are definitely within specifications for the PXI-6259, and if you notice a sound from the chassis, it is due to the fans, which I agree with you it can be very loud. The fact a slight change in frequency would produce a different sound from the chassis is rather strange. Not sure if it's just the noise volume that increases, or if it's like a high pitch sound changing.

What would be more useful is that you record this noise to a .wav file (hopefully good quality audio) and upload it here, to determine if the sound is normal or not.