Application Areas - Siemens 3UG4 User Manual

4.2

Application areas

The 3RR2 current monitoring relays are used, for example, in the following applications:
● Monitoring for current overshoot and current undershoot
● Monitoring for cable breaks
● Monitoring for no-load operation and load shedding (as might be the case, for example, in
the event of a torn V belt)
● Underload monitoring in the lower performance range (if a pump was running in no-load
operation, for example)
● Monitoring for overload (as might affect pumps with a soiled filter system, for example)
● Monitoring the performance of electrical loads such as heaters
● Monitoring for incorrect phase sequences on mobile equipment such as compressors or
cranes
● Monitoring for high-impedance faults to ground (caused by damaged insulation or
moisture, for example)
Table 4- 1
Function
•
•
•
•
•
•
•
•
3UG4 / 3RR2 monitoring relays
Manual, 05/2016, NEB927043002000/RS-AC/004
Application areas of the 3RR2 current monitoring relays
Undercurrent
Overcurrent
Apparent current
Active current (3RR22 only)
Phase failure / wire break
Phase sequence (3RR22 only)
Internal ground fault detection (fault
current) (3RR22 only)
Block current (3RR22 only)
3RR2 current monitoring relays
Application
Emergency lighting
•
Heating systems (electroplating plants, plastic injection
•
machines, paintshops)
Lamps (tunnels, OR lighting, traffic lights, signal
•
systems, UV lamps, infrared radiators, laser lamps)
Fan
•
Pumps
•
Sawing system
•
Conveyor belt
•
Surface grinding machine
•
Breaking mill
•
Milling machine
•
Car wash
•
Lifting platform
•
Screw conveyor
•
Crane
•
Turning machine
•
Woodworking
•
Grain mills
•
Steel industry
•
4.2 Application areas
47