Dold BA9065.20 3AC220-254V 0,1-2A | Cos phi monitoring, Part N: 0041153

The underload monitor BA 9065 measures the phase shift between voltage and current. The phase angle changes with changing load. This measuring method is suitable to monitor asynchronous motors on underload and no load independent of motor size. The change of cos ϕ has to be bigger then the hysteresis of the monitor. In some cases the cos ϕ does not change much with load change on the motor. Monitors underload and no load on squirrel cage motors e.g.

• fan monitoring (broken belt)
• filter monitoring (blocked filter)
• pump monitoring (blocked valve, dry running)