ExCom Intrinsically Safe I/O
Excom® is a remote I/O system intended for use in Ex and non-Ex areas. It comprises bus-compatible remote input and output modules in IP20 for connection of binary and analog intrinsically safe field devices. Depending on the installed periphery, the system's protection category allows the application in the zones 1, 2 and the non-Ex area. The field circuits are approved for use up to zone 0. The system consists of power supplies, gateways, I/O modules as well as module racks to accommodate all Components. The backplane is integrated in the module rack. It is needed for power supply, data transport and contains the connection plane for the field devices. The power units supply the entire system. One power supply unit is enough for correct system operation.
Module Racks
The module racks are composed of a backplane and the actual rack system. They accommodate gateways, power supplies and up to 24 I/O modules. They are implemented in the combined Exe and Exi protection rating. The supply of power to the modules on the backplane is limited in order to prevent sparking. This allows you to pull and plug modules in powered state withexcom® mounted in zone 1.
Power Supply
The power supply modules feed the entire system. Only one power supply module is needed for proper operation. To increase availability, a second power supply module can be plugged (redundancy). The supply voltage is 24 VDC, when using 230 VAC or rather 115 VAC use a ballast to convert voltage to the admissible input values.
Digital modules
The digital modules are designed for connection of NAMUR sensors (EN 60947-5-6) or rather intrinsically safe actuators such as valves or indicators. When wire-break and short-circuit monitoring are activated, mechanical contacts can only be connected with a corresponding resistor circuitry (WM1, see accessories).
Analog modules
The analog input modules of the excom® system are intrinsically safe and can take up to four transmitters. HART® capable sensors can be connected to them, which communicate directly with the integrated HART® controller (HART® modules). The analog output modules are designed for connection of intrinsically safe analog actuators such as control valves or process indicators.
Gateways
The gateways act both as a master to the internal data bus and as a slave to the higher level fieldbus. They control the entire data exchange between the I/O modules and the process logic control system (PLC). To increase availability, a second gateway can be plugged (redundancy). When connecting a DP master toexcom® always use a segment coupler with the RS485-IS layer.
SS Panel for Hazardous Area Installation
- If the system is to be installed in zone 1, the system enclosure must be Exe approved, IP54 or higher.
- If the system is to be installed in zone 2, the system enclosure must at least be IP54 rated, EN 60079‑0 and EN 60079‑15 must be observed.
Follow the installation guide, when mounting the excom® Components in an EN 60079-0 approved enclosure. Possible heat generation inside the enclosure must be considered when installing the Components. Installation and assembly have to be carried out by the manufacturer in order to ensure that the required distances as well as clearances and creepage are met.