Cold Switching. Closing the relay contacts before applying voltage and current and removing voltage and current before opening the contacts. (Contacts do not make or break current.是什么意思_Cold Switching. Closing the relay contacts before applying voltage and current and removing voltage and current before opening the contacts. (Contacts do not make or break current.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句