VIN voltage drops

Hello,

I have an odd issue, maybe power or ground reference related.

XC43 IQAN 6.08, sensors powered using the main 24VDC not regulated VREF.

When I start driving valves with the module the reported voltage from my VIN sensors drops by up to 5%.

It happens to all of them irrespective of the sensor type.

It also jumps around a ton.

This makes a huge difference on my 0-5800 0.5-4.5V sensors.

200+ PSI, not good for sensor accuracy.

Any ideas of what to try to fix?

Regards,