Significant factors include regulation of line voltage, temperature of the room in which the device operates, temperature control, and condition and age of the lamps.
主要的因素包括：线路电压的调节、设备房间室温、控制的温度、条件以及灯的寿命。
2
And it has the features of wide range regulation of voltage, simple circuit, output stability, reliability, excellent interactive interface, being widely used and so on.
具有电压调节范围宽，电路简单，输出稳定，可靠性强，人机交互接口优良，应用范围广泛等特点。
3
Because of the pure resistive nature of the equivalent resistance of impedor, no harmonic will be generated during the voltageregulation.