The FT027 is a replacement part for the FT742-DM range of wind sensors. Located within the sensor support column, this EPDM O-ring (3.53 CS x 32.92 ID) is fitted as standard during manufacture to provide additional water ingress protection. In the event of damage (or general replacement), it can be replaced with care by a technician using tweezers.
The FT742-DM sensor is intended for installation on a 33.7mm mounting pipe (EN 10255) with some resistance offered by the internal O-ring (provided for ingress protection). It is important to ensure the FT033 Tapered Pipe Insert is bonded into the mounting pipe to avoid damage to the O-ring on sensor installation and provide a smooth transition onto the pipe. The O-ring sits within an internal groove, marked below with a yellow arrow:
Refer to the FT742-DM product manual and the following Application Notes for further information:
A4166-1 FT742-DM Accessories
A4167-1 Lightning Guidance