xa2 voltage drop

Ed Schippers 6 years ago in Expansion modules / XA2, XS2 updated by Gustav Widén (System support) 6 years ago 1

Due to a voltage drop in the system, because of an electric fan switching on, all the voltage inputs give a low error.

The strange thing is that the voltage drop is not so big. it drops from 27 to 22 for only a sec due to the high start current of the fan.

Is this normal, I thought the modules could be used in 12 VDC system also. So the voltage drop should not be a problem.



Only the voltage drop on the supply to the XA2 will not cause a problem like this. 

If I would take a guess, it sounds a lot like a problem with a ground offset between the sensors and the XA2. If this large starting current runs so that the XA2 ground potential is lifted 5V relative to the sensor ground, you would have this symptom.

Are the sensors installed with +VREF and -VREF from the XA2 that has the VIN:s? 

With external supply and ground to the sensors the symptom you describe would be more likely.