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What is TSM and PSM of a relay and how to calculate

Relay Time Setting Multiplier and Plug Setting Multiplier calculation

Relay time setting multiplier (TSM) and plug setting multiplier (PSM) are the two key parameters required to calculate the operating time of the relay. Having knowledge of these two is very important in order to understand the relay operation. 
Remember These two terms are related with the IDMT type relay, they are irrelevant for the definite type relays. 
So let's know about the relay TSM and PSM 
What is Time Setting Multiplier (TSM) : TSM or Time Setting Multiplier of relay is defined as the ratio of actual operating time to the ideal operating time (operating time obtained from PSM vs Time graph).
Some time it is also written as Time multiplier or TMS.

What is Plug Setting Multiplier (PSM) 
PSM or Plug Setting Multiplier is defined as the ratio of fault current from CT secondary to the pickup current of the relay.

Remember : pickup current is the minimum current required to start the relay operation. 

For exampl…

Ohms law calculator | Calculate Voltage power Resistance and Current

What is ohms law calculator (online): It is basically a calculator based on the principle of ohm's law. You can calculate the third parameter of any dc circuit , if the other two parameter a circuit is known to you.

(Go to the bottom to take part in the ohm's law Top 10 mcq quiz)

The three main parameters are Voltage (V) , Current(I) and Resistance (R). And the relation between them is V=I*R.

Here in this calculator you can additionally calculate the 4'th most important  parameter of any circuit, that is power (P).
DC Ω - Ohm's Law Calculator Voltage (V)Volts (V)Resistance (R)Ohms (Ω)Current (I)Amps (A)Power (P)Watts (W)ResetHelpCalc © Copyright Czigler Ferenc All Rights Reserved. How to use Enter any two variables in the fields.Click Calc button. How to calc Ohm's law: Wikipedia pageElectric power: Wikipedia page
Statement of ohms law : "The ratio of potential difference (V) between any two points on a conductor to the current (I) flowing between them is constan…

Calculate resistance with resistor colour code calculator

Calculate resistance with resistor colour code calculator

Graphical Resistor Calculator Graphical Resistor Calculator is a Free Software to easily calculate the resistance of registers from the band colors.
Simply change the values from the dropdown menus.
Band 1Band 2Band 3Band 4Value 1 (MSV)Value 2WeightToleranceBlack (0)Brown (1)Red (2)Orange (3)Yellow (4)Green (5)Blue (6)Violet (7)Gray (8)White (9)Black (0)Brown (1)Red (2)Orange (3)Yellow (4)Green (5)Blue (6)Violet (7)Gray (8)White (9)Black (1)Brown (10)Red (100)Orange (1k)Yellow (10k)Green (100k)Blue (1M)Violet (10M)Gray (100M)White (1G)Gold (± 5%)Silver (± 10%) Resistance:  1,000 Ω ±5%
Graphical Resistor Calculator Reference Chart Standard Table For Calculating 4 Band Resistors' Resistance.
ColorDigit valueMultiplierMultiplied OutToleranceBlack01001Brown110110Red2102100Orange31031,000Yellow410410000Green5105100,000Blue61061,000,000Violet710710,000,000Gray8108100,000,000White91091,000,000,000Gold±5%Silver±10% Content resistanc…

Top 10 Electrical Engineering MCQ |

Test your self with our Top 10 electrical engineering MCQ question


All about Star Delta winding connection

What is star and delta connection?
There are mainly 2 types of 3 phase winding connection, namely the star or Wye (Y) connection and the delta or D connection.
The Star or Y connection:
If we connect the each end of winding to a common point and The rest of the three points of three windings are connected to the supply , to form a Y shaped 3 phase winding then it is said to be star connected winding. 

The star winding has some special characteristics, these are:
In case of star winding each phase winding carries 1/√3 times the phase to phase / line voltage.Each of the winding carries current that is equal to the load currentIt has a common neutral point , and so that it can supply 3 phase as well as single phase loadGenerally it is the distribution part
* Here the term 'phase current/voltage' means the current/voltage that is flowing through each of the winding and the term load current/ voltage stands for the current/voltage that is applied across the load or supply terminal The D…