Before starting the installation, plan carefully how many support arms you need and where to install them. The number and positioning of support arms depends on the sensors that you are going to install.
The support arm is a horizontal bar that is used for mounting the following types of sensors:
- Humidity and temperature probe
- Present weather detector
- Solar radiation sensors
- Wind sensor
For most sensors, WMO recommends installation at 2 meters (6 feet 7 inches) from ground level. Install the support arm as close to this height as possible. Take also into account the mast type: on a tiltable mast, install the support arm so that it does not prevent lowering and erecting the mast.
For sensor-specific guidelines on positioning and aiming the sensor, see the sensor installation instructions.
| To prevent corrosion, oxidation, and seizing, use a non‑conductive, non‑water‑soluble, non‑silicone‑based grease, such as ceramic or Teflon paste, between different kinds of metal. |