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## Intrinsic stand-off ratio for UJT as oscillator Thyristor firing circuit Solution

STEP 0: Pre-Calculation Summary
Formula Used
Intrinsic stand-off ratio UJT as Oscillator = Emitter resistance base 1/(Emitter resistance base 1+Emitter resistance base 2)
η = RB1/(RB1+RB2)
This formula uses 2 Variables
Variables Used
Emitter resistance base 1 - Emitter resistance base 1 is the resistance offered to the current flowing through the base 1 junction on UJT. (Measured in Ohm)
Emitter resistance base 2 - Emitter resistance base 2 is the resistance offered to the current flowing through the base 2 junction on UJT. (Measured in Ohm)
STEP 1: Convert Input(s) to Base Unit
Emitter resistance base 1: 10 Ohm --> 10 Ohm No Conversion Required
Emitter resistance base 2: 5 Ohm --> 5 Ohm No Conversion Required
STEP 2: Evaluate Formula
Substituting Input Values in Formula
η = RB1/(RB1+RB2) --> 10/(10+5)
Evaluating ... ...
η = 0.666666666666667
STEP 3: Convert Result to Output's Unit
0.666666666666667 --> No Conversion Required
0.666666666666667 <-- Intrinsic stand-off ratio UJT as Oscillator
(Calculation completed in 00.016 seconds)

## < 10+ Thyristors Calculators

Excess work due to thyristor 1 in chopper circuit
Excess energy in chopper circuit = 0.5*Reverse di/dt limiting inductance*((Load current of chopper circuit+(Reverse recovery time*Commutation capacitor voltage)/Reverse di/dt limiting inductance)-(Load current of chopper circuit^2)) Go
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
Resultant series voltage of thyristor string = Number of thyristors in series thyristor string*Voltage across thyristor 1 in thyristor string-(Number of thyristors in series thyristor string-1)*Resistance*Off state current spread of thyristor string Go
Maximum Thyristor gate voltage for resistance firing circuit
Maximum gate voltage = Maximum AC input voltage*(Stabilizing Resistance/(Stabilizing Resistance+Variable Resistance+Resistance)) Go
Derating factor of series connected thyristor string
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Power dissipated by heat in SCR
Power dissipated by heat in SCR = (SCR junction temperature-SCR ambient temperature)/Thermal resistance of SCR Go
Thermal resistance of SCR
Thermal resistance of SCR = (SCR junction temperature-SCR ambient temperature)/Power dissipated by heat in SCR Go
Leakage current of the collector-base junction
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Discharging current of dv/dt protection thyristor circuits
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### Intrinsic stand-off ratio for UJT as oscillator Thyristor firing circuit Formula

Intrinsic stand-off ratio UJT as Oscillator = Emitter resistance base 1/(Emitter resistance base 1+Emitter resistance base 2)
η = RB1/(RB1+RB2)

## Explain important UJT parameteres?

RBBO : It is the resistance between the terminals B1 and B2. In simple words, it is the resistance of the N-Type bar when measured lengthwise. If RB1 is the resistance of the bar from E to B1 and RB2 is the resistance of the bar from E to B2, then RBBO can be expressed as RBBO= RB1 +RB2. The typical range of RBBO is from 4KΩ to 10KΩ.

Intrinsic standoff ratio (η) : It is the ratio of RB1 to the sum of RB1 and RB2. It can be expressed as η = RB1/(RB1+RB2) or η = RB1/RBBO. The typical range of intrinsic standoff ratio is from 0.4 to 0.8.

## How to Calculate Intrinsic stand-off ratio for UJT as oscillator Thyristor firing circuit?

Intrinsic stand-off ratio for UJT as oscillator Thyristor firing circuit calculator uses Intrinsic stand-off ratio UJT as Oscillator = Emitter resistance base 1/(Emitter resistance base 1+Emitter resistance base 2) to calculate the Intrinsic stand-off ratio UJT as Oscillator, The Intrinsic stand-off ratio for UJT as oscillator Thyristor firing circuit formula is defined as the ratio of emitter base 1 resistance to the total emitter base junctions resistances. Intrinsic stand-off ratio UJT as Oscillator is denoted by η symbol.

How to calculate Intrinsic stand-off ratio for UJT as oscillator Thyristor firing circuit using this online calculator? To use this online calculator for Intrinsic stand-off ratio for UJT as oscillator Thyristor firing circuit, enter Emitter resistance base 1 (RB1) & Emitter resistance base 2 (RB2) and hit the calculate button. Here is how the Intrinsic stand-off ratio for UJT as oscillator Thyristor firing circuit calculation can be explained with given input values -> 0.666667 = 10/(10+5).

### FAQ

What is Intrinsic stand-off ratio for UJT as oscillator Thyristor firing circuit?
The Intrinsic stand-off ratio for UJT as oscillator Thyristor firing circuit formula is defined as the ratio of emitter base 1 resistance to the total emitter base junctions resistances and is represented as η = RB1/(RB1+RB2) or Intrinsic stand-off ratio UJT as Oscillator = Emitter resistance base 1/(Emitter resistance base 1+Emitter resistance base 2). Emitter resistance base 1 is the resistance offered to the current flowing through the base 1 junction on UJT & Emitter resistance base 2 is the resistance offered to the current flowing through the base 2 junction on UJT.
How to calculate Intrinsic stand-off ratio for UJT as oscillator Thyristor firing circuit?
The Intrinsic stand-off ratio for UJT as oscillator Thyristor firing circuit formula is defined as the ratio of emitter base 1 resistance to the total emitter base junctions resistances is calculated using Intrinsic stand-off ratio UJT as Oscillator = Emitter resistance base 1/(Emitter resistance base 1+Emitter resistance base 2). To calculate Intrinsic stand-off ratio for UJT as oscillator Thyristor firing circuit, you need Emitter resistance base 1 (RB1) & Emitter resistance base 2 (RB2). With our tool, you need to enter the respective value for Emitter resistance base 1 & Emitter resistance base 2 and hit the calculate button. You can also select the units (if any) for Input(s) and the Output as well. Let Others Know