The profundimeter is a device that assesses the pressure to which it is subjected, indicating the depth to which it is located. It is an essential device for the diver, as it allows the diver to control the depth at which it is along with the immersion.
CAPILLARY TUBE PROFUNDIMETER
Although currently fallen into disuse, the simplest and cheapest is that of capillary tube, which however gives very accurate readings in small depths.
Water enters through the end of a transparent capillary tube and depth is indicated as the water line moves within the tube along the depth scale.
The graduation is very spaced at the beginning (the first 10m occupy half the scale) but gradually compresses so that the accuracy decreases as the depth increases.
BOURDON TUBE PROFUNDIMETER
Bourdon tube mechanical profundimeters, although without the same precision in the first meters, have the advantage of being more precise at greater depths.
In this equipment, the depth is indicated by a pointer, which moves on a scale that can have uniform graduation or exponential evolution.
On aircraft journeys without a pressurized cabin, these profundimeters must be transported in a watertight box, as they may be damaged.
Digital, electronic-devised profundimeters are very accurate at any depth, and depth indication is read on a digital display. The profundimeters of this type memorize the data of the last dives, namely the maximum depth reached during the dive, the length of stay at the bottom, the temperature, whether the rate of ascent has been respected, the time interval between dives, the longest depth recorded by the device, among other information. Although these devices warn you when the battery starts to be low, we must take into mind the level of the battery charge, so that we do not have the unpleasant surprise of us being without any kind of information dUrante the dive. As depth is one of the fundamental information for the diver, the profundimeter should not be used as a simple object of adornment, but to be read with some frequency. This device can be worn on the wrist, like any watch, or installed on a multi-instrument console.