I’m looking for info for VMB4AN - what’s the resolution of A/D converter?
That suggests it might be 16 bit:
Do you want to connect to my rig again and use NodeRed to view the packets to decode the resolution?
Thank you! I have a VBM4AN on the way to me, so I’ll be able to check it locally. I was hoping for some internal info 
to calculate what resolution I will get with temp. and level sensors.
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Some background information (and not an answer to the question posed here…)
On one hand bit width is not well defined for every type of ADC: this is an artifact of how certain types (e.g. SAR) of ADCs are implemented – other types such as sigma-delta don’t really have that as a well defined quantity. Though I would be surprised if Velbus used an ADC that isn’t based on the SAR architecture.
On another the sampling bit width (& output bit width) does not necessarily reflect the accuracy or precision of the ADC. More than often, SAR ADCs sample 12 or 14 bits worth of analog signal level and it is possible to to get more precision by taking multiple samples with multiple successive samples providing the additional couple bits of precision (this in particular is an attempt to strike a balance between the implementation cost, sampling speed and flexibility.)
Finally, quality of ADC implementations tend to vary greatly. You could have an ADC that samples 16 bits (i.e. is precise) but produce output more noisy than a high quality 12-bit ADC. With Velbus I’d hope they use a high quality ADC implementation with a primary focus on accuracy and a secondary one on precision. But I don’t really have a skin in this game as I haven’t any use cases for VMB*AN.
Thank you very much! You know much more than me about it. I know the theory part from the schools 