A practical example... control and supervision of extraction wells
In the Oil&Gas market it is fundamental to have control and supervision of what occurs in the extraction areas. That's why the wells are controlled by remote using a specific SCADA system that allows to supervise the areas of interest in the different extraction wells located in the territory. It is not always possible to install an optical fiber network to transfer data due to high costs and obstacles faced in setting up.

A very important client requested us a different solution to create a network redundancy for the SCADA system that deals with the control and supervision of 26 gas extraction wells in Algeria. The suggested standard radio for the coverage of these wells is the TETRA. This kind of trunked radio standard is designed for medium-size areas with a high density of users and it is the most suitable to transfer the data coming from the RTU, thanks to the ‘IP packet data’ version conceived just for information transfer.

The fundamental problem is to connect two devices such as TETRA Motorola MTM800 Radio Base, that handles the transmission of data to the DCS in the control station, to thethird parts RTU, that collects data from the devices. In that specific case, the Yokogawa RTU uses the Modbus communication protocol. Therefore there is a problem of interconnection between the third parts RTU operating in the Modbus protocol and the radio network TETRA.
The solution proposed by Sinora consists in placing between the TETRA MTM800 Databox radio base and third parts RTU a device that allows the communication between them. The device used is the RTU Motorola ACE3600.
This equipment has different features such as powerful processor, a large variety of input/output modules and the possibility of direct connection of Intelligent Electronic Devices(IED), that make it perfect for that scenario. The ACE3600 RTU is connected in standard ‘Modbus over ethernet’ to the third parts RTU and in ‘MDLC over RS232’ protocol to the TETRA radio base. This device acts as interpreter between the TETRA Motorola base station and the third parts RTU that command all devices from an extraction well.

This interconnection is made possible by a software integration carried out by Sinora to the ACE3600 device. This software patch deals with the elaboration of data received according to the Modbus standard and to make them available to the MTM800 base station in the MDLC protocol it supports. 
The integration between the TETRA radio network and the SCADA gas extraction wells network was performed in a clear way compared to DCS and the remote third parts RTU. 26 Motorola MTM800 Databox, 27 RTUs Motorola ACE3600 and 4 Motorola (3 MTS1 e 1 MTS4) base stations were supplied.
The proposed solution created a network redundancy for the SCADA used in Algeria for the telecontrol of the devices placed in the 26 locations of gas extraction. The TETRA radio network is designed as an excellent carrier for the data transfer; the transported information are useful for the supervision and control of the system becausa it allows to transmit such data in a reliable and efficient way.

In particular, the MTM800 Databox radio base was considered for this data transfer through the radio TETRA ‘IP packet data’ protocol because it allows to a fast and effective information transport by dedicating an entire time slot just for this purpose.
The supplied SCADA system on the TETRA network is a cost effective solution that allows to save a lot of money compared to a optical fiber network infrastructure. Moreover, customer will take advantage of performance, in terms of band and delays, requested by the SCADA system without any compromise. In addition the same TETRA network can be used in the normal voice communication between workers located in the various extraction wells.

104 Motorola MTP850Ex portable devices were provided to the customer; these devices are specifically designed for explosive environments. The proposed interconnection system is versatile thanks to the use of the RTU Motorola ACE3600 that can interface with all the RTU already installed via the RS-232, RS-485 serial ports, Ethernet ports, but also via Modbus RTU communication protocols, DF-1, DNP3+, IEC 60870-5-101, MDLC, TCP, UDP, IP, PPP, NTP, and DHCP.
The RTU ACE3600, thanks to its performance and features, can directly manage the data acquisition and the control of both analog and IED devices, without having to interconnect to a third parts RTU. 
For this solution we used...