Information about Electric Tester Circuit.

[huzeeigat]

Hello Everyone,

Please provide me with info on the basic Electric tester circuit which we use in our homes to test live and neutral connections,and which also comes in-built in a screw-driver with a small neon l.e.d. If anyone has any links of how the circuit works please post it here..Need it urgently.

Thanks,
Huzefa

 

[jiripolivka]

Hello Everyone,

Please provide me with info on the basic Electric tester circuit which we use in our homes to test live and neutral connections,and which also comes in-built in a screw-driver with a small neon l.e.d. If anyone has any links of how the circuit works please post it here..Need it urgently.

Thanks,
Huzefa

This simple tester contains a neon glow-lamp with a series resistor, ~100 kOhms. The lamp glows if there is >100 V AC or DC between screwdriver tip and the back contact (or a black wire to connect to ground).
You connect the back contact to ground (often your body makes for it) and try the tip on live (lamp glows) or neutral (lamp does not glow).

Some training with a skilled electro technician is recommended.,

 

[huzeeigat]

This simple tester contains a neon glow-lamp with a series resistor, ~100 kOhms. The lamp glows if there is >100 V AC or DC between screwdriver tip and the back contact (or a black wire to connect to ground).
You connect the back contact to ground (often your body makes for it) and try the tip on live (lamp glows) or neutral (lamp does not glow).

Some training with a skilled electro technician is recommended.,

Jiripolivka any idea of how much current would be flowing through the neon lamp..? Also wanted to know why the human body does not feel the electric shock when we touch the tester..?

 

[FvM]

This simple tester contains a neon glow-lamp with a series resistor, ~100 kOhms.

As a minor correction, testers used in the 230 VAC world rather have 500k to 1 Meg series resistors, I see e.g. 820k with my device.

any idea of how much current would be flowing through the neon lamp

Ohms law applies.

 

[huzeeigat]

Okay so the current would be in the range of around ~0.4mA - ~0.23mA... Also wanted to know will the neon light be sufficient to drive a phototransistor if the circuit is isolated in a housing. If possible provide me with details of different phototransistors..

Thanks in advance,