The Autonics LR5N Rate Meters are among several process meters available from Automation Systems and Controls . These Rate Meters are self powered units which have a replaceable lithium battery.
The LR5N rate meters can display RPM, RPS or frequency. They also have a flexible input range of 30-240 vac or non contact, NPN, or PNP. This compact unit W48 x H24 is small in size but is big on features.
These Autonics Rate Meters are ideal for measurement of machinery speed or counting using a time base.