Water gauges

[Thomas]

Hello
Water gauges returns pulses only. I can send these pulses through KNX bus and count them in LM.
But how to do it correctly?
If I use GO  only then I can't do backup and restore for example.
If I store values on SD card after every pulse I'm in risk I will kill it quickly.

How do you solve this problem?

[Erwin van der Zwart]

Hi,

Writing to storage is not direct to SD so could not hurt the SD.

What i do in this case is use a KNX interface of Schneider MTN670802 and set it to impuls counter, it then counts the impulses internally and you can write the counted values over x period to the bus on a set interval.

In the controller i get random values like 30, 40, 35 depending on the number of counted pulses in the set period and i sum them to the old value, this way you don't need to process every puls on the controller but you do it in batches.

BR,

Erwin

[Thomas]

Hi,

Writing to storage is not direct to SD so could not hurt the SD.

What i do in this case is use a KNX interface of Schneider MTN670802 and set it to impuls counter, it then counts the impulses internally and you can write the counted values over x period to the bus on a set interval.

In the controller i get random values like 30, 40, 35 depending on the number of counted pulses in the set period and i sum them to the old value, this way you don't need to process every puls on the controller but you do it in batches.

BR,

Erwin

But still you need a storage for the counter. Do you store it on SD card?
Because both options are wrong in sobe way
GO - backup and restore is impossible
SD - changing of SD is complicated

Some mix of both? I mean compare GO and SD and higher number wins seems to be a good choice.

[Daniel]

Storage function will save your value in to Redis DB which runs in RAM. It saves everything to SD or SPI (depend of the hardware version) every half an hour like everything else.