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Goals and Symptoms
What kind of application is this relay RM35S0MW built for?
How to use it ?
Is there some limitation?
Facts and Changes
Causes and Fixes
Speed Measurement and Control Relay
The relay counts the time between each pulse and evaluates the speed.
This value is compared with the preset value to determine whether if the system is under or over speed. The pulse interval can vary from 0.05 seconds to 10 minutes
The main application are escalators, monitoring of rotation speed, transporter or conveyor belt speed, pump rotation, industry process systems..
Interval between pulses (measurement range) corresponds to frequency (Hz) and speed (rpm):
Time Frequency (Hz) Frequency (rpm)
0.05 to 0.5s 2 to 20 120 to 1200
0.1 to 1s 1 to 10 60 to 600
0.5 to 5s 0.2 to 2 12 to 120
1 to 10s 0.1 to 1 60 to 6
0.1 to 1 mn 0.017 to 0.178 1 to 6
0.5 to 5 mn 0.033 to 0.33 0.2 to 2
1 to 10 mn 0.0017 to 0.017 0.1 to 1
A relay can only control one characteristic: Undervoltage or Overvoltage.
You cannot do both. On the other hand, you must use 2 relays and select it with the knob N°1. Then you select the range (Knob N°3) and adjust % (Knob N°2) according to the speed to control.
A speed 900rpm corresponds to 15Hz(900/60) and then to a time of 0.067s. You select with the knob N°3 the time range 0.05 to 0.5s and the select 13.33% with knob N°2
Currently, we do not have another relay that control a speed higher than 1200rpm.
If you have a speed higher, you can use a reduction gear