The more powerful the fishfinder, the more possibilities it has; to reach the bottom and to outline it in more detail.
It is expressed in Watt RMS (or more rarely in peak Watt) and indicates the power with which the transmitter (inside the fishfinder) sends electrical impulses to the transducer.
The greater the power of the fishfinder, the greater the possibility of probing deeper seabeds, provided that the disturbance emitted does not increase.
So the more powerful a fishfinder has a powerful transmitter, the more quality the fishfinder will be. This is especially true on deeper seabeds and generally does not adversely affect shallower seabeds, because the user has the ability to adjust the sensitivity of the receiver (some even the transmission power).
Maximum power and depth
There are no rules for determining the maximum depth that can be reached by an echosounder, knowing its power and frequency, because other parameters such as the sensitivity of the receiver or the ping rate (almost always unknown) are necessary.
It is often stated that a depth sounder can reach 400 m depth with a transmission power of 600 W RMS and a frequency of 50 KHz. But manufacturers such as Lowrance deny this rule, thanks to the use of a receiver with very high sensitivity that on a transmission of only 32W RMS can even read over 400 m. even if the best results in terms of detail are achieved with these fishfinders in the shallow.
In addition, when determining the maximum depth, the chemical/physical factors of the water in which you are going to operate must be carefully considered. For example, elements such as salinity, temperature, viscosity and turbidity are factors that strongly affect the possibility of the echo returning from the bottom and in some cases the combination of these factors can also lead to a reduction of 10 times the maximum depth achievable.