Technical Description – OilGuard Ex M
Oil in bilge water IMO certified discharge monitor
The OilGuard Ex M for Oil discharge monitoring (ODME) of ODME for slop tank and bilge water overboard discharge and complies with the IMO standard MEPC.107(49) Guidelines and Specifications for Pollution Prevention Equipment for Machinery space Bilges on Ships and 46 CFR 162.050.
The OilGuard Ex M works on the fluorescence principle. The design uses a non-contact measuring cell that eliminates contact between the sample and the flow cell. This ensures that the measuring cell remains clear from contamination and the drift in results that follows. If water doesn’t touch optics, the windows won’t foul.
A Closer Look
The OilGuard Ex M is the most dependable instrument available for monitoring potential pollution from bilge water in hazardous environments and with extremely low maintenance. Let’s explore 2 important reasons how we can confidently make this statement.
Non-contact measuring cell
Other Oil In Water instruments use a system where the water is in contact with the measuring cell. Despite various cleaning methods, the windows will require routine cleaning. By using a non-contact method, there is no longer a requirement for cleaning. Having its typical “belt and braces” approach, Sigrist have also fitted a PVDF sleeve over the PVDF nozzle to eliminate splashing. Stainless steel is also available, but care must be taken in its application. Ask us which is the preferred nozzle for you.
Ease of Maintenance
The measuring cell is not part of the pressurised enclosure. The only thing inside the measuring cell is the sample water flow and the UV light beam. This means that 2 thumb screws can open the measuring cell for inspection and calibration.
The instrument can be returned to factory calibration using the included highly stable, mono-crystalline calibration checking unit. Recalibration requires no consumables or tools to return the instrument back to factory calibration.
Sigrist uses an inorganic, extremely low expansion, non-porous Lithium Aluminium Silicon oxide glass ceramic characterized by evenly-distributed nano-crystals within a residual glass phase. It is designed and manufactured to exacting Sigrist specifications to provide:
- Excellent homogeneity throughout the total volume.
- Very low level of inclusions and internal stress deformations
- Precision shapes
- Extremely smooth polished surface (< 1 nm roughness)
- Excellent long term chemical stability
So what does this mean to you? Well, you already know that the accuracy of what you measure is only as good as the ruler with which you measure. That same principle of technology that has gone into this calibration crystal. It means that you can return your instrument to Sigrist Factory calibration accuracy with no cost, no consumables, and in very short time, and (with some instruments) using none of your valuable maintenance time. That statement is so significant, it’s worth reading again.
The Specs at a Glance
|Measuring principle||Fluorescence measurement|
|Enclosure||Stainless steel (DIN 1.4301 / AISI?? 304)|
|Protection class||Ex II 2G Ex px IIC T4 (zone 1)|
|Flow cell material||PVDF|
|Sample flow rate||4 – 6 l/min|
|Calibration||according to IMO resolution MEPC.107(49)|
|Supply voltage||230 V; 50/60 Hz|
|Power input||150 VA|
|Sample temperature||max. 95 °C|
|Sample pressure||Atmospheric pressure through the measuring cell|
|Interfaces||Profibus DP (optional)|
|Purge air||6 l/min to maintain pressurised enclosure|
|Ambient environment||-20 to + 40 °C (optional max. +50 °C)|
|Analog outputs||4-20 mA (max. 600Ω/max. 24V)|
|Warm-up time||minimum 2 hours|