ThingsLogTM can measure consumption from meters with pulse output. In order to understand how does it work let’s first focus on what is a pulse.
Figure 1 illustrates a pulse output.
Each pulse is characterized with an amplitude and a T_high and T_low. T_high is the duration of the pulse and T_low is anytime between two pulses.
The pulses are generated in the meter by a sensor that responds to a magnet that rotates on the face of the meter under the lens. The sensor turns on and off once each time the magnet passes under it.
Depending of your meter one pulse might mean different things:
- For water meters 1 pulse = 1 L, 10 L or 100 L, e.g one pulse is equal to 1, 10 or 100 liters of water
- For gas flow meters 1 pulse = 0.01 m3, 0.1 m2 or 1 m3, e.g one pulse is equal to 1/100, 1/10 or 1 cubical meter of natural gas
- For electricity energy typically you will get something like 1, 10, 100, 1000 W. E.g one pulse is equal to 1, 10, 100 or 1000 Watts.
Note: It is always better to get a meter with pulse output than a mater with integrated radio metering module. The integrated module typically could be read only by the vendor of the meter and the pulse output by anybody able to detect a pulse as the one above.
Note: It is always better to get a meter able to generate pulses on smaller quantities of water, gas or electricity. That will allow us to perform fine-grained monitoring and get your consumption right.
How does a meter with pulse output look like?
As you can see to the meter is attached a small device with a cable snapped on it. This is the pulse output. Our data loggers has inputs for pulse metering devices which should be connected to the pulse output of the meter.