Ukraine acdc power module potting requirements(2)

Epoxies cannot be used for stress-sensitive and module sealing due to their hardness and are basically eliminated by module power supplies. However, due to its low cost, this epoxy is still used in cost-sensitive micropower supplies. Some domestic bad 24V input power supply manufacturers also use this epoxy resin acdc 24V input power supply module. However, due to stress problems, the failure rate of this 24V input power supply is very high, and buyers are miserable.

At present, the most commonly used power module is the addition of silicone. This kind of silica gel is generally 1:1, which is easy to operate. When acdc potting power modules, attention should be paid to its thermal conductivity. However, the bonding ability is not very strong, and it can be improved with primer.

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

Polyurethane has been used in China for a period of time, but due to its high hardness, inconvenient maintenance, and the price reduction of silicone rubber, the cost performance of polyurethane is not high.