What is a barograph used for?
Unlike a traditional barometer, a barograph allows you to visualize pressure changes over several days.
It provides a precise reading of weather trends and allows you to anticipate changes in the weather.
How does a barograph work?
A barograph works using aneroid capsules sensitive to pressure changes.
The mechanism amplifies these movements and records them on a rotating diagram.
To what value should you set your barograph?
This tool allows you to accurately determine the atmospheric pressure for your location of use in order to correctly calibrate your instrument.
Select the scale currently displayed on your barograph, then click on the map at the location of your instrument.
The adjustment value will automatically appear.
All you have to do is adjust your barograph until the tip of the inker indicates this value.
How to adjust your barograph?
New NAUDET Devices
Our barographs are factory-calibrated according to the altitude of the place of use.
An adjustment can be made using the focus knob. The focus knob is located at the bottom of the column, closest to the cylinder, on the front of the device (A).
It allows adjustment of the measurement within a range of approximately ±300 meters from the initial setting.
Beyond this range, a workshop intervention is necessary to modify the mechanism.
The counterweight (B), present on some models, is only used to balance the weight of the pen. It is not an adjustment element and should not be tampered with.
Other brands or older devices
For other models, the adjustment may differ, particularly for devices from other brands such as Maxant, Jules Richard, or for older Naudet models.
In this case, we invite you to send us photos of your device so that we can provide you with suitable and precise advice.
How to interpret your curve?
The barograph continuously records variations in atmospheric pressure, making it possible to anticipate weather changes.
A rise in the curve generally indicates an improvement in weather conditions.
A drop in the curve indicates a deterioration in the weather.
A sharp drop in the curve within a few hours indicates the arrival of strong winds and may presage a storm.
When the curve is stable, the weather remains unchanged.
A gradual variation, up or down, is generally associated with a lasting change in the weather, whether it is an improvement or a deterioration.
December 1999 Storm Chart
How to change your chart, pen, or feather?
Diagram
To change your chart, turn the needle recoil (C); this part allows you to lift your pen from the chart.
Once clear, pull the paper bar (B) upwards.
Take a new chart, position it around the cylinder, joining its two ends at the closing line of the paper.
Replace the bar in its slot.
The charts are printed on special paper designed specifically for use with pens or styluses.
Using charts printed on regular paper will consume your pen's ink quickly and could create ink smudges on your charts.
Pen
To change your pen, turn the needle recoil (C).
After carefully removing your old ink cartridge by pulling it parallel to the nib, position the new one by sliding it in until it locks into place; there is no need to force it.
For proper operation, it is essential that the pen rests lightly on the paper.
To ensure this, tilt the barograph slightly so that the pen lifts off the paper.
If it does not, you will need to loosen the adjustment screw (D).
Pen
To change your pen, turn the counter-clockwise screw (C).
Remove the pen by pulling it parallel to its holder.
If it is stuck, soak it in 90° alcohol to soften the ink and facilitate its removal.
Then insert the new one by sliding it until it stops, without forcing it.
The pen should rest lightly on the paper. If necessary, tilt the barograph to check that it lifts off; otherwise, slightly loosen the adjustment screw (D).
Clean the pen regularly to prevent it from clogging.
Soak it in 90° alcohol.
How your barograph's cylinder works
Recent barographs are equipped with 7 cm or 9 cm high drums.
Some older formats existed, with different operating mechanisms.
If you have any doubts about your model or if your device does not correspond to the descriptions below, we invite you to send us a photo of your barograph.
We can then advise you precisely.
Download small model instructions
PDF - For printing