VMB4AN - detailed config

I was wondering if there was a more detailed guide on using the VMB4AN - I’ve connected a sensor (24V Amp based) … in the Velbus Link I see the current value 1514… but it also states Sensor Not Configured. I did configure the sensor to send it’s information every 10 seconds

so, I’m trying to configure it… essentially - (or more importantly) it needs to be able to provide the value through Velbus to OpenHab where I can convert the value received to M3 water available in my tank… but the values for sensor 1 in OpenHab are either Voltage or “Analog Input” - which is a point-string type… that one stays NULL for now…

Good morning.

A couple of things to consider here.

1 the Velbus module configuration.
2 how openHAB deals with it.

Firstly, you need to configure the sensor in the VMB4AN.

Defining what type of sensor it is and then editing the plot points so that the VMB4AN can interpret the value returned from the sensor into a useful value.

You say it’s a 24V powered sensor, but don’t say if it returns a 4~20ma value, a 0~10v or pulses.

(By the fact you have a value displayed, we must assume you’ve got something set)

The next thing to do is edit the plot points and define a “Unit of Measurement”
For example

0 pulses = 0 ltr per minute
1000 pulses = 10 ltr per minute


0v = 0v
10v = 240v


0v = 0% humidity
10v = 80% humidity

I have a water depth / pressure sensor that works out along these lines
4ma = 0M³
20ma = 40M³

If you know what your sensor value of 1514 really means, you should be able to create some plot points.

While you’re in that configuration window, define how often the module will broadcast the sensor value to the bus.
(It will always respond to a poll)

If you’ve set the Item in openHAB correctly, you should start seeing values shortly afterwards.

FYI: The configuration of the sensor must be configured in VelbusLink and written to the module. If you do that, it will convert the current value which you’ve already seen into a measured and calculated sensor value. If not, the VMB4AN doesn’t know what the sensor represents.

yups… managed to configure it - it’s current based and it provides an output now in OpenHab…

next is calibrating - to determine the current for empty (water) tank … full watertank provides me 7780uA…

I just think the manual can be a bit more detailed… :wink: - but wrote my own: Velbus Modules and their connections – Velbus UAE (wordpress.com)

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