What is the role of the wholesale?(3)

Input protection circuit General customized non-standard Marine boost voltage power supply customized module (factory supply products use built-in filters, which can meet the requirements of general Marine boost voltage power supply applications. If a more demanding power system is required, wholesale the input filter network should be added. Either LC or π can be used but care should be taken to choose a smaller inductance and larger capacitance.

Remote control switch circuit
The remote control switch operation of the module power supply is carried out through the REM terminal. There are two general control methods:
(1) REM is connected to -VIN (reference ground), the remote control is turned off, and VREF<0.4V is required. REM is suspended or connected to +VIN, the module works, and VREM>1V is required.
(2) REM is connected to VIN, the remote control is turned off, and VREM<0.4V is required. REM is connected to +VIN, the module works, VREM>1V is required. REM is suspended, and the remote control is turned off, that is, the so-called "suspended shutdown" (-R).
If the control is to be isolated from the input, an optocoupler can be used to pass the control signal

In order to prevent the transient high voltage damage of the customized non-standard Marine boost voltage power supply customized module (factory supply, it is recommended that the user connect the transient absorption diode to the input terminal, and cooperate with the fuse to ensure that the module is within the safe input voltage range. In order to reduce the common mode noise, Y (Cy) can be increased and several capacitors nf high frequency capacitors are generally selected. R is a fuse, D is a protection diode, and D is a transient absorption diode (P6KE series).