This model CDV is designed for cooling circuit survey, or survey of any high pressure circuits, to protect pumps against flow less accidents. 

The fluid moves over an orifice plate with a built-in magnet. A compensating spring allows the mounting in any position. CDV operates without incidence of pressure on measurement, even with low flow rates. The diver indicates the flow rate through a graduated glass tube. A Reed contact is adjustable all along the scale. The contact is Normally Open (opened with flow less conditions).