Protection Relays Current Monitoring Relays and Transducers LSRU SERIES Load sensor Description The LSRU Series is a microcontroller-based family of load sensors. The LSRU family of products employ three basic types of control logic: motor control logic, alarm logic and feed control logic. Motor Control Logic Several combinations of functions are available in the LSRU, including overcurrent and undercurrent or either overcurrent or undercurrent with variable trip, restart or extended restart delay settings. These various versions of the LSRU trip on the respective fault and then automatically reset after the restart delay expires, in preparation for the next motor start. LSRUs do not trip on undercurrent when the load turns off, this is recognized as a normal condition. Wiring Diagram Alarm Logic The LSRU-AL simply indicates whether the current is between the setpoints or outside of the setpoints. This product is best used with a PLC or other controller where status indication is desired. Feed Control The LSRU-FC is a load monitor intended to control feeder mechanisms in a variety of applications. It stops the feeder when the grinder, chipper, saw, auger, etc. nears overload. When the load is reduced to a preset level, the feeder is restarted. Features & Benefits FEATURES Visual indication of relay status Built in current sensor Eliminates the need for a stand alone current transformer and also provides isolation between the monitored and control circuits Adjustable current sensing range Provides ability to precisely set the current trip point for any application Ordering Information See next page. © 2016 Littelfuse Protection Relays & Controls www.littelfuse.com/lsru

Ordering Information MODEL LINE VOTAGE CURRENT RANGE DESCRIPTION PART#KEY O = Overcurrent Trip 1.5 = 0-10 Amps U = Undercurrent Trip 2 = 5-25 Amps T = Adj. Trip Delay (0.5-60 seconds) 3 = 25-100 Amps R = Adj. Restart Delay (0.5-300 seconds, Manual) E = Adj. Extended Restart Delay (2-300 minutes, Manual) Specifications Functional Characteristics Isolation Power Motor Acceleration Time When not selected as an option: Fixed Trip Delay (-AL,-FC) Fixed Restart Delay (-AL only) (-FC only) Input Characteristics Control Power Output Characteristics Output Contact Rating (SPDT) Pilot Duty General Purpose...