Motor load monitoring relays

Efficient load monitoring of asynchronous motors 

The motor load monitoring relay monitors the load states of single-phase and three-phase asynchronous motors. Compared with other conventional measuring principles (e.g. pressure transducers, current measurement), the cos ϕ monitoring is a more precise and economical alternative. It measures the voltage of all three phases, the current of one phase and calculates the phase angle (cos ϕ) between them to evaluate the status of the motor.

Main benefits

• Down time reduction
• Easy commissioning
• Easy maintenance

Main features

• Under- and overload monitoring cos ϕ in one unit
• Adjustable start-up delay 0.3-30 s
• Direct measurement of currents up to 20 A
• Adjustable response time delay 0.2-2 s
• Single-phase or three-phase monitoring
• 2 x 1 c/o contact, closed-circuit principle