Doubles have twice the dynamic load rating of single units and can be mounted in place of the singles in most applications due to similar mounting footprint.
双打有两倍的动态负载率和单一的单位，可以安装到位的单打在大多数应用中由于越来越多类似的足迹。
2
Ensure that the total ampere ratings on all units plugged into the extension cord is not above the cord's rating.
确保插在电源器上的电源线范围数不要超过额定数，也不要超过总的额定电流。
3
Certain recommendations are given about vitalizing national economy, retrofit of obsolete units and development of advanced domestic manufactured power equipment of large rating.