Technical solution for integrating Elster water meters into AMR systems using DTU data loggers.

Elster H4000 and S2000 water meters are widely distributed worldwide and are actively used for commercial water accounting in industrial facilities and utilities. A significant advantage of these meters is their high accuracy in registering both forward and reverse flow of the liquid, which opens up numerous use cases for the application of this equipment.

However, these meters lack standard interfaces for connecting to Automatic Meter Reading (AMR) systems. This issue is typically addressed by equipping the meters with special retro-fit inductive type modules, such as Elster PR7. With an open collector output, the PR7 module can be connected to a data logger with a pulse input for further transmission of data to AMR systems.


One such solution is the DTU series of data loggers, designed to collect readings from metering devices and transmit data to the cloud platform via GPRS or NB-IOT networks, depending on the data logger model.

All DTU data loggers have pulse inputs and can be connected to the "open collector" output of the PR7 module for meter reading collection. When selecting the appropriate data logger model, please pay attention to the K-factor of the used PR7 module (see Table 1).

For clarity, we provide a connection diagram for the CH2P channel (compensated output) of Elster PR7 to DTU1xx and DTU3xx (Figure 1). Using the same diagram, the CH1P channel can be connected to capture all registered pulses regardless of direction, allowing you to determine the magnitude of the reverse flow.

PR7 output typeADGT supported model
K1DTU2xx, DTU4xx
K10, K100DTU1xx, DTU2xx, DTU3xx, DTU4xx
Table 1. Correspondence of DTU models to PR7 output types based on K-factor.


Connection diagram of PR7 to DTU1xx and DTU3xx
Figure1. Connection diagram of PR7 to DTU1xx and DTU3xx

Collected meter readings and other diagnostic data are transmitted to the cloud server based on a freely configurable schedule.

Thus, our solution enables remote monitoring of metering devices with PR7 modules and the extraction of consumption data for further transmission to calculation centers.

Typical solution diagram. Connecting DTU data loggers to PR-7 pulse modules for reverse flow monitoring in water metering systems