The modbus gateway from J. Dittrich Elektronic transforms the analog 4-20 mA measured signals of the company's gas measuring systems into digital signals and serially transmits them via an RS485 interface to a control centre, which can be up to 1000 m away.
For this, the gateway is using the modbus RTU protocoll, a common, clearly structured, stable and reliable protocoll.
Using this protocoll, the single modbus gateways are hanging on the data bus like linen on a clothes line and transmit their data only upon request of the control centre (so-called master slave architecture).
A maximum of four gas measuring systems can be connected to each modbus gateway via four channels. Therefore the digital signal contains the following information: identification of the gateway, channel, measured gas, measured value.
