We connect instruments in hazardous areas to the control system by limiting the energy that enters the zone, so that no circuit fault can cause ignition. Applicable to zones 0, 1 and 2, with galvanic isolation and safety functions up to SIL 3 per IEC 61508.
In a plant with gas or combustible dust, a transmitter, a valve or a pressure switch can become an ignition source if the loop delivers more energy to the field than the zone allows. The consequence is not a production stop but an explosion, with risk to people and a plant shut down until the investigation is closed. The most common deviations are Zener barriers whose intrinsic safety earth is not checked periodically, and loops assembled without validating compatibility between the interface, the instrument and the cable. These conditions do not affect daily operation, so they usually go unnoticed until an audit or an incident.
We start from the area classification, not from the catalogue.
Zone, gas or dust group and temperature class per IEC 60079-10-1 and AEA 90079.
We check the interface parameters against those of the instrument and the cable.
We integrate the right technology from our partners for each loop.
The core of the pillar: the interface between the instrument in the hazardous area and the control system card. It limits energy to the field and, with galvanic isolation, breaks ground loops and protects the control system from a field fault. Selection depends on the signal type (analog, digital, temperature or HART), the zone, and whether the loop is part of a safety function.
A safety system is only as reliable as its power supply. It requires redundant supplies with load sharing that keep delivering power if one fails, suitable for zone 2 mounting and extreme temperatures. Selection depends on total power, the integrity level the system requires and the cabinet environment.
Closing a valve, stopping a compressor or shutting in a well depends on a relay between the control system and the actuator. A standard relay is not certified for the loop's integrity level and may read as a fault the test pulses the control system uses to check its own outputs. The solution is a safety relay certified along its whole path, from coil to contact, and compatible with those pulses.
Modern transmitters report their own status, but that information usually stays in the field because the control system does not process it. A multiplexer brings diagnostics from hundreds of instruments to a maintenance station without changing the existing architecture. This makes it possible to detect an instrument's degradation before it fails and to plan the proof tests a safety instrumented system requires.
A loop that leaves the control room and runs across the plant to a tank or a tower acts as an antenna for surges induced by lightning. The surge reaches the interface and the instrument, and can leave unprotected the area the loop was meant to safeguard. It is solved with surge protectors dedicated to instrumentation loops, certified for Ex zones, at both ends of the loop.
We help you size the right solution for your plant.
Which machine, process or installation do you need to solve? Five questions, no more.