Level Transmitter Attains European Type Approval on Steam Drums

The second generation of Magnetrol’s (Belgium) Eclipse 705, 2-wire Guided Wave Radar approved to the newest European norms for steam drums, EN 12952-11 (water tube boilers) and EN 12953-9 (shell type boilers) as “primary safety ” and “secondary safety” device. These norms complete the PED construction guidelines with functional directives, typical for use on steam drums. The Eclipse 705 has been type approved by the Dutch “Stoomwezen”, for use on steam drums as a secondary safety device since 2002. As a secondary safety device, Eclipse fulfills all general control functions on the steam drum; such as the controlling of the hot feed water to the boiler. In its function of ‘primary safety’ device, Eclipse operates as a safety switch and turns off the boiler in a safe way in case an emergency / dangerous situation occurs. The number of primary and secondary safety devices on a steam drum depends on the type of boiler, the manning of the boiler (permanently manned, semi-manned or not manned at all), its process pressure, capacity, etc ….

The Eclipse 705 combines two major advantages against the traditionally used transmitters; high reliability – repeatability and an efficient process seal. The Eclipse uses the technology of Guided Wave Radar. This measuring principle measures independently of the process parameters such as density, conductivity, dielectrics, pH, etc. High pressure and temperature changes inside a boiler have an important impact on the accuracy and reliability of the traditional transmitters such as differential pressure, displacer and RF capacitance. The process seal of the 7MS probe is specifically designed for use on saturated steam. The dynamics of the seal take the sudden and aggressive changes of process pressure and temperature into account.

The Eclipse 705 with 7MS probe resists a process pressure of 155 bar at an equivalent temperature of +345°C in saturated steam applications. For non-steam applications, Eclipse can be used on process conditions from –196°C up to +430°C / full vacuum up to 430 bar. The Eclipse 705 transmitter can be configured for both measuring level and liquid-liquid interface in level units or volume units.

The Eclipse 705 is also available with a SIL2 version. The additional diagnostic tools allow the user to integrate this transmitter within high demanding safety instrument loops. With a SFF (Safe Failure Fraction) of 91%, Eclipse is the only TDR transmitter on the market that scores as high on safety level. The Eclipse 705 (with enhanced SIL electronics) is suitable for SIL2 loops as 1oo1 device (hardware fault tolerance 0 – FMEDA analyzed by Exida per IEC 61508).