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What can meterN do for you ?

meterN aim is to monitor meters like electrical energy ones. It simply needs to retrieve the total quantity counter value, this reading is done on a 5 min basis.

Some first thoughts

You can set up either : meter and sensor logger and also indicator. The 'Meter' type is used for.. meters ;), 'Sensor' is to monitor any values such as a temperature or an humidity. 'Indicator' is simply for showing a live value that don't need to be recorded, like voltage or frequency

Configuring meters and sensors

When you'll be configuring a meter, you are required to set a main 'Command' that will return the total quantity (eg: Total Liter, Total Watt per hour, Total m³, ..). For a sensor, that could be any value (eg: Temperature, Voltage, ..).

Then you can also set a 'Live command', a non-mandatory value to be shown on the dashbord. meterN will retrieve this one continously, the refreshing time will depend mostly on your communication application.
It will show an instantaneous value (eg: Liter per minute, Watt, ..) or it could also show a text, like a device status (eg: On/Off, Hot/Lukewarm/Cold, Charging/Discharging, ..).

But wait, we need to speak a common language first !

The output format of the communication(s) application(s) must respect JSON format or the IEC 62056 data set structure, that look scary but it is quite simple :
 
ID ( VALUE * UNIT )


It is the same format used in, the better know, "P1 interface" a communication interface available in some smart meters for local communication utility use.
 
Some valid outputs :
1(10923*Wh)water(6903*l)1-0:1.8.1(00737044*Wh)0-1:24.3.0(00643.165*m3)
temp(19.3*°)humid(60.3*%)tarif(cheap*Wh)battery(charging*Wh)

 
 
 
 Important notes :
- meterN need to get the values without any unit prefix. eg: elect(39464*Wh) is valid. elect(39.464*kWh) is not.
- For decimal values, only points (not commas) shall be used
- Front "(" and rear ")" boundary characters are needed as well as the separator character "*" between value and unit
- The meter counter can't reset to 0 (eg. after a surge), it should always increase until it pass-over.

Now than you've understand how meterN discuss with a communication application, you are ready to set-up !

When you'll start the admin. interface (see the tour), you had to set :

- A meterID corresponding to your meter dataset ID eg: elect
- A 'Main pooling' command for the communication application that return a quantity value. eg: elect(10923*Wh)
- A precision value. It's the meter's resolution, the numbers behind the unity. eg: 3 for a 0.001m³ accuracy
- A pass-over value, it's the value up to where the counter can count until it return to zero. It can be disabled by putting it to zero, you counter will always increase then.
- The dashboard pooling, it's where the (non mandatory) live values will be shown :
Outputs eg: elect(256*W), boiler(on*) or even boiler(<font color='#228B22'>On</font>*x) if you wish some colors

House's electrical consumption and production

If you own a electrical consumption and/or production unit, you can setup a such meters. It will allow to visualize the electical energy flow with the main gauge and in the dashboard .


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