Monitoring Relays

Monitoring relays are a type of relay that trips a circuit breaker when a fault is detected. A relay is an electrically controlled switch that is used to turn the power on or off in a circuit. 




Monitoring relays are more sophisticated than regular relays, as they have adjustable operating conditions, whereas normal relays switch according to a fixed threshold. They measure a given parameter, such as voltage or temperature, and will trip a circuit breaker when the parameter gets too high or low. 




What are monitoring relays used for?


Monitoring relays have a wide range of uses, depending largely on the factor being monitored. For example, they can protect against overcurrent if measuring current, or they can detect an abnormally low frequency if frequency is being measured.




Types of monitoring relay


The main way in which monitoring relays differ is the function that they measure. This can be a number of things, including:



  • voltage

  • current

  • temperature

  • frequency


The factor that you need to measure will decide which monitoring relay you choose.


...
Read more Read less

Filters

Viewing 1 - 20 of 56 products
Results per page
Description Price Monitoring Application Supply Voltage Contact Configuration Voltage Sensitivity Electrical Phase Voltage Sensing Range Current Sensitivity Minimum Current Sensed Maximum Current Sensed Phase Sensitivity Time Delay Temperature Sensitivity Temperature Sensing Range Frequency Sensing Range
RS Stock No. 145-960
Mfr. Part No.RM35LM33MW
$228.96
Each
units
- 20.4 → 264 V ac/dc - - - - - - - - - - - -
RS Stock No. 124-0193
Mfr. Part No.RM35LM33MW
$83.81
Each
units
Level 20.4 → 264 V ac/dc DPDT - 1 - - - - - 0.1 → 5 s - - -
RS Stock No. 146-480
Mfr. Part No.RM35TF30
$431.46
Each
units
Phase, Voltage 220 → 480 V ac DPDT Overvoltage, Undervoltage 3 194 → 528 V ac - - - Phase Asymmetry, Phase Failure, Phase Sequence 0.1 → 10 s - - -
RS Stock No. 146-238
Mfr. Part No.RM17TG20
$193.80
Each
units
Phase 208 → 440 V ac DPDT - 3 - - - - Phase Asymmetry, Phase Failure, Phase Sequence <100 ms - - -
RS Stock No. 146-597
Mfr. Part No.RM17TU00
$204.00
Each
units
Phase, Voltage 208 → 480 V ac SPDT Undervoltage 3 183 → 528 V ac - - - Phase Failure, Phase Sequence 0.1 → 10 s - - -
RS Stock No. 776-3648
Mfr. Part No.A9E16065
$339.07
Each
units
Time Delay 24 V dc, 24 → 240 V ac SPDT - - 24 → 240 V ac - - - - - - - -
RS Stock No. 124-0190
Mfr. Part No.RM22UB34
$228.42
Each
units
Voltage 60 → 280 V ac DPDT Overvoltage, Undervoltage 1 80 → 300 V ac/dc - - - - 0.1 → 30 s - - -
RS Stock No. 146-452
Mfr. Part No.RM17UB310
$291.94
Each
units
Voltage 208 → 480 V ac SPDT Absence of Neutral, Overvoltage and Undervoltage Between Neutral, Overvoltage and Undervoltage Between Phase 3 183 → 528 V ac - - - - 0.3 → 30 s - - -
RS Stock No. 146-143
Mfr. Part No.RM35UA12MW
$229.65
Each
units
Voltage 24 → 240 V ac/dc DPDT Overvoltage, Undervoltage - 1 → 100 V - - - - 0.3 → 30 s - - -
RS Stock No. 146-092
Mfr. Part No.RM17JC00MW
$248.80
Each
units
Current 24 → 240 V ac/dc SPDT - - - Overcurrent 2A 20A - 0.5 s - - -
RS Stock No. 776-3657
Mfr. Part No.A9E16066
$308.95
Each
units
Time Delay 24 V dc, 24 → 240 V ac SPDT - - 24 → 240 V ac - - - - - - - -
RS Stock No. 145-976
Mfr. Part No.RM35JA32MW
$273.21
Each
units
Current 24 → 240 V ac/dc DPDT - - - Overcurrent, Undercurrent 0.15A 15A - 0.3 → 30 s - - -
RS Stock No. 124-0184
Mfr. Part No.RM22TR33
$235.45
Each
units
Phase, Voltage 304 → 576 V ac DPDT Overvoltage, Undervoltage 3 380 → 480 V ac - - - Phase Failure, Phase Sequence 0.1 → 30 s - - -
RS Stock No. 146-250
Mfr. Part No.RM17TG00
$177.99
Each
units
Phase 208 → 480 V ac SPDT - 3 - - - - Phase Asymmetry, Phase Failure, Phase Sequence <100 ms - - -
RS Stock No. 124-0182
Mfr. Part No.RM22LG11MR
$160.97
Each
units
Level 20.4 → 264 V ac/dc DPDT - 1 - - - - - <0.6 (Run-Up) s - - -
RS Stock No. 146-200
Mfr. Part No.RM35JA31MW
$224.14
Each
units
Current 24 → 240 V ac/dc DPDT - - - Overcurrent, Undercurrent 2mA 500mA - 0.3 → 30 s - - -
RS Stock No. 124-0185
Mfr. Part No.RM22TU21
$114.29
Each
units
Phase, Voltage 160 → 288 V ac DPDT Undervoltage 3 200 → 240 V ac - - - Phase Failure, Phase Sequence ≤650 (Run-Up) ms - - -
RS Stock No. 609-8081
Mfr. Part No.LT3SM00MW
$723.02
Each
units
Temperature 24 → 230 V ac DPDT - - - - - - - - Overtemperature, Undertemperature - -
RS Stock No. 146-519
Mfr. Part No.RM17UBE15
$225.38
Each
units
Voltage 110 → 240 V ac/dc SPDT Overvoltage, Self Powered, Undervoltage 1 65 → 260 V ac/dc - - - - 0.1 → 10 s - - -
RS Stock No. 124-0192
Mfr. Part No.RM35JA32MT
$223.62
Each
units
Current 323 → 456.5 V ac DPDT - 3 - Overcurrent, Undercurrent 150mA 15A - 0.1 → 30 s - - -