The Eletta PR1 Paddle Switch is using the liquid flow to activate the spring supported paddle and the micro-switch to give an alarm if the flow stops or starts. PR1 can be used in pipe sizes from DN50 to DN250 and the set point is dependent on the length of the paddle and the pipe size, please refer to the table below. The installation is simple as you can cut the paddle to the desired length on site according to the actual pipe size. The paddle aligns fully with the flow and creates a very small pressure drop. The function works only in one flow direction. Wetted parts is made of Copper Alloy and Stainless Steel and the sealing of Nitrile (HNBR).