The BRAUN Single Channel Speed Monitor Series D521.xx monitors motors, pumps, feeders, gears, rollers, and small turbines. It provides protection against overspeed at any required value of rotational speed, including standstill.
The universally designed signal input fits perfectly with BRAUN A5S… sensors or equivalent. However, it can also be used with NAMUR-type sensors, tacho generators, incremental encoders, or magnet-inductive sensors (MPUs).

With single-channel processing (1oo1) safety provision is solely determined by the device configuration. Therefore the use of sensor monitoring with integrated plausibility control is essential. In such a case no redundancy is provided. Should a fault be detected, the entire system will be shut down immediately.
With two-channel systems, there is a choice of implementation, dependent upon requirements. In principle, the two monitors operate in parallel yet independently. Alarm indication can be realized through the linkage of their Alarm Outputs.

For 1oo2 processing, we have system redundancy with enhanced safety through comparative diagnosis. In the case of fault detection, the entire system will be shut down. With 2oo2 processing, we still have system redundancy but with enhanced availability. Only if both monitors fail, the system as a whole will be shut down.
The D521 Speed Monitor permanently monitors the speed sensors for their correct function. During its complete lifetime cycle, the Monitor does not require any external proof tests and is completely maintenance-free.

•Single Channel Monitor with sensor monitoring and self-test function
•Universal Signal Input, also for Magnetic Pick-Up sensors (MPUs)

Parameter Name	Parameter Value
Type	speed
Applications	measurement alarm rotary machine
Other characteristics	digital inductive