27FEM610 | PROCESSMASTER | OI/FEM610-EN REV. A6 CommissioningSafety instructions Write-protection switch, service LED andlocal operating interfaceWrite protection switchIf write protection is active, the parameterization of thedevice cannot be changed via the local operating interface orthe local display.Turning the write protection switch clockwise deactivates thewrite protection while turning the switch counter-clockwiseactivates it.Service LEDThe service LED, which indicates the operating condition ofthe device, is located in the sensor terminal box.Local operating interfaceThe sensor can also be parameterized without a local displayvia the local operating interface, see chapter"Parameterization via the local operating interface" onpage 29.Aggressive or abrasive measuring medium may result indamage to the wetted parts of the flowmeter sensor. As aresult, pressurized measuring medium may escapeprematurely.Due to wear on the flange seal or process connection gaskets(e.g., threaded pipe connections, Tri-Clamp, etc.), apressurized measuring medium may escape.When using internal flat gaskets, these can becomeembrittled through CIP/SIP processes.If there is a chance that safe operation is no longer possible,take the device out of operation and secure it againstunintended startup.Risk of burns due to hot measuring mediaThe device surface temperature may exceed 158 °F (70 °C),depending on the measuring medium temperature.Before starting work on the device, make sure that it hascooled sufficiently.CAUTIONWrite protection switchService LEDLocal operating interface123Figure 38 Write-protection switch, serviceLED and local operating interfaceG12019123Service LED DescriptionFlashes rapidly (100 ms) Starting sequence, device not yet ready foroperationLit up continuously Device operating, no critical errorFlashes slowly (1 second) A critical error has occurred, see chapter"Diagnosis / error messages" on page 62