Detection of(resistor) resistance up to their tolerance limit...ok or not?

[MD SALIM AREEB]

Dear sir,
I want to develop the economic & simple circuit for just to know the particular resistor (only 1K 5%) is having their range under the tolerance limit or not.

Means:

• IF THE RESISTOR CROSSES THEIR LIMIT LIKE (Either+ve side more than 1050E Or -ve side less than 950E) Buzzer or LED indication should has to come AS A Out put for alert.
• IF THE RESISTOR NOT CROSSES THE LIMIT or having under the tolerance range o/p not required.

(THIS IS ONLY FOR THE INWARDS GOODS INSPECTIONS FOR carbon film resistor )

Thanks
Salim Areeb

 

[Nigel Goodwin]

Google 'window comparator'

 

[alec_t]

Some (at least) of your measuring circuit components may have to have tolerances much smaller than 5%. What are the limits on your limits? For example, is '5%' anywhere from 4.9% to 5.1%? ....or what? The exact range of acceptability is important in the economics of accepting/rejecting the goods.

 

[crutschow]

As alec_t noted you need to be concerned about the accuracy of your measurement circuit which likely should be in the neighborhood of 0.5% or better. You likely need to have pots so you can calibrate the upper and lower set points of the circuit using an accurate and known resistive load, such as one of these.

 

[ronsimpson]

Salim Areeb, Is this home work?

The "10 volts" could be a 9V battery. The voltage does not mater much.
Pots are there to set the plus and negative limits.
If R2 (unknown) is 1000 ohms the center voltage will be 1/2 supply.
If R2 is off by 5% then you can work out how much the voltage moves.
The two voltage comparators look at (1/2 supply-5%) and (1/2 supply+5%).

Just in case it is home work......How will you change things to get only one output. (out of range)