Hello everyone, I might need your help.
The stepper motor(OYOSTEPPER) used in an outdoor surveillance pan-tilt unit experiences a drop in insulation resistance to several megohms every morning, which recovers to tens of megohms as temperatures rise during the day.
Upon disassembly, there is no condensation inside the motor, but there are trace amounts of water droplets on the inner wall of the junction box. Analysis suggests this is due to the diurnal temperature difference causing a “breathing” effect, with moisture entering the junction box at night and condensing in the morning.
Although no short circuit has occurred, this repeated process over time will corrode the terminals and insulation. Completely sealing the junction box with sealant is risky as it prevents airflow inside the motor, potentially causing pressure differences due to thermal expansion and contraction.
Is there a junction box solution with a breathable membrane that can both prevent moisture and balance pressure?
I’m constantly worried that the insulation might break down and burn out the driver.
