We are concerned that the output terminal is equipped with a metal cover. Is it safe to use it as it is?

How to Use Power Supply FAQ

There is no problem whatsoever. In fact, the chassis (or base plate) of the power supply is made of metal and grounded for sure. Therefore, the metal cover of the output terminal attached to the chassis also maintains grounding to secure safety. Likewise, although there are bare cooper terminals in the bus bar type, the inside of the output terminal cover is designed to galvanically isolate the equipment.