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## Circuit turn off time Class B commutation Solution

STEP 0: Pre-Calculation Summary
Formula Used
Circuit turn off time Class B commutation = Capacitance*(Thyristor commutation voltage/Load current)
toff = C*(V/Io)
This formula uses 3 Variables
Variables Used
Capacitance - Capacitance is the ratio of the amount of electric charge stored on a conductor to a difference in electric potential. (Measured in Farad)
Thyristor commutation voltage - Thyristor commutation voltage is defined as the magnitude of voltage at which a thyristor gets commutated. (Measured in Volt)
Load current - Load current is defined as the magnitude of the current drawn from an electric circuit by the load connected across it. (Measured in Ampere)
STEP 1: Convert Input(s) to Base Unit
Thyristor commutation voltage: 10 Volt --> 10 Volt No Conversion Required
Load current: 5 Ampere --> 5 Ampere No Conversion Required
STEP 2: Evaluate Formula
Substituting Input Values in Formula
toff = C*(V/Io) --> 3*(10/5)
Evaluating ... ...
toff = 6
STEP 3: Convert Result to Output's Unit
6 Second --> No Conversion Required
6 Second <-- Circuit turn off time Class B commutation
(Calculation completed in 00.016 seconds)

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Worst case steady state voltage across first thyristor in series connected thyristors
Worst case steady state voltage of thyristor 1 = ((Resultant series voltage of thyristor string+(Number of thyristors in series thyristor string-1)*Resistance*Off state current spread of thyristor string))/Number of thyristors in series thyristor string Go
Voltage across first thyristor in series-connected thyristors
Voltage across thyristor 1 in thyristor string = (Resultant series voltage of thyristor string+(Number of thyristors in series thyristor string-1)*Resistance*Off state current spread of thyristor string)/Number of thyristors in series thyristor string Go
Resultant series voltage of series connected thyristor string
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Thermal resistance of SCR
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### Circuit turn off time Class B commutation Formula

Circuit turn off time Class B commutation = Capacitance*(Thyristor commutation voltage/Load current)
toff = C*(V/Io)

## Explain Class B commutation in thyristors?

Class-B or Resonant Pulse Commutation is a forced commutation technique to turn off an SCR. In this technique, thyristor or SCR is turned off by gradual build-up of resonant current in the reverse direction i.e. from cathode to anode of SCR. This technique is also known as current commutation and occurs in DC circuit not in AC circuit.
The commutation circuit comprises of Capacitor C, Inductor L and an auxiliary thyristor TA. Initially thyristor T1 and TA are in off state and capacitor C is charged to voltage Vs with left hand plate positive.

## How to Calculate Circuit turn off time Class B commutation?

Circuit turn off time Class B commutation calculator uses Circuit turn off time Class B commutation = Capacitance*(Thyristor commutation voltage/Load current) to calculate the Circuit turn off time Class B commutation, The Circuit turn off time Class B commutation formula is defined as the time required by the thyristor circuit to turn off for class B commutation. Circuit turn off time Class B commutation is denoted by toff symbol.

How to calculate Circuit turn off time Class B commutation using this online calculator? To use this online calculator for Circuit turn off time Class B commutation, enter Capacitance (C), Thyristor commutation voltage (V) & Load current (Io) and hit the calculate button. Here is how the Circuit turn off time Class B commutation calculation can be explained with given input values -> 6 = 3*(10/5).

### FAQ

What is Circuit turn off time Class B commutation?
The Circuit turn off time Class B commutation formula is defined as the time required by the thyristor circuit to turn off for class B commutation and is represented as toff = C*(V/Io) or Circuit turn off time Class B commutation = Capacitance*(Thyristor commutation voltage/Load current). Capacitance is the ratio of the amount of electric charge stored on a conductor to a difference in electric potential, Thyristor commutation voltage is defined as the magnitude of voltage at which a thyristor gets commutated & Load current is defined as the magnitude of the current drawn from an electric circuit by the load connected across it.
How to calculate Circuit turn off time Class B commutation?
The Circuit turn off time Class B commutation formula is defined as the time required by the thyristor circuit to turn off for class B commutation is calculated using Circuit turn off time Class B commutation = Capacitance*(Thyristor commutation voltage/Load current). To calculate Circuit turn off time Class B commutation, you need Capacitance (C), Thyristor commutation voltage (V) & Load current (Io). With our tool, you need to enter the respective value for Capacitance, Thyristor commutation voltage & Load current and hit the calculate button. You can also select the units (if any) for Input(s) and the Output as well. Let Others Know