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Reading electricity meter Landis+Gyr ZMF 120AC impulses for RRDtool logging
Branje impulzov iz LandisGyr stevca ZMF 120AC po RS232 protokolu.
Konstanta stevca 500 imp/kWh. Dolzina impulza 40ms
Leon Kos, 2011
RS232 adapter with 20 meters of phone cable between meter and Linux server
requires two components: R1 provides pulldown. D1 reverse voltage protection.
DB9 RS232 Connector
___
TxD | 3 |---+
| | |
| | | | R1
| | | | 1K5
| | | |
| | | blue/white
RxD | 2 |---+----------------------+