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Why telephone line has negative voltage?

Anonymous

∙ 10y ago

Updated: 4/28/2022

A negative live voltage is used to prevent electroytic corrosion on the copper wires.

Wiki User

∙ 10y ago

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Q: Why telephone line has negative voltage?

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Continue Learning about Electrical Engineering

Is percent voltage regulation can be negative?

yes.. voltage regulation can be negative

What is negative 48 volt DC voltage?

Negative 48 volt DC voltage is simply a voltage that is negative 48 volts with respect to ground. This voltage is widely used in telecommunication systems.

What is the significance of negative values of voltage and current?

What is the significance of negative values of voltage and current?Negative values show direction and that is the significance

Why tan delta test give negative values?

The reason is that internal voids within the insulation will discharge as the voltage rises; once discharged, they will not do so again at some higher voltage. if all voids become discharged, theoretically the plot of tan delta versus voltage would level off to a horizontal line. In effect, tip-up becomes "negative".

What is the UK 3 phase voltage?

The nominal voltage in the UK is 400/230 V. That is 400 V line-to-line (i.e. line voltage), and 230-V line-to-neutral (i.e. phase voltage). Allowable variation is +10% and -6%.

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Related Questions

Why a lamp cannot run with the telephone line voltage?

A lamp can be run by power from a telephone line.

What is the voltage of a telephone line?

48 VOLTS

Does an oscilloscope display both positive and negative voltage?

Yes. By convention, the horizontal line is deflected upward for positive voltages and down for negative. With no input, adjust the line to co-incide with a central line on the graticule. A varying voltage that remains positive will be deflected above the line. A voltage that transits from positive to negative will draw above and below the line.

What is the voltage of telephone line in Pakistan ptcl?

it has 52volt dc off hook

Why is every telephone set powered by a negative voltage?

so that they still work after you power goes out

What is the voltage of telephone line?

I'd say it wouldn't be -40 volt, but in fact 40 volt. I'm guessing you measured it with a multimeter and had your polarity (positive/negative) mixed up when you placed the leads on the telephone line. -------------------------------------------------------------- The nominal voltage between tip and ring on the telephone line is 48 VDC (it is provided by a 24 cell lead acid battery in the central office) but this can be reduced by line drop by as much as 9 VDC depending on how far you are from the central office. Tip is connected to the positive side of the battery and ring is connected to the negative side of the battery. The tip and ring twisted pair is isolated from ground, so either can be used as your multimeter reference as long as you are aware of polarity so the reading of the multimeter will make sense.

A telephone-repair technician uses a meter to measure voltage on a phone line. This meter is an example of .?

it is hardware not software

Is percent voltage regulation can be negative?

yes.. voltage regulation can be negative

How many volts can a landline telephone handle without blowing?

Since the ringer voltage across the twisted pair is 120 VAC RMS the telephone can definitely handle that. Given the fact that the telephone is also supposed to survive induced surges from nearby lightning strikes to the line the telephone should be able to handle over 1000 V common mode impulses (but I don't know the exact limit). No telephone is expected to survive a direct lightning strike to the line (which could be millions of volts). Note: common mode means the voltage is applied between the twisted pair lines (both at about the same voltage) and ground. If the survivable common mode voltage were to be applied across the twisted pair instead it would severely damage the telephone.

When measuring voltage how should test probes be connected?

The red test probe is typically connected to the positive terminal and the black test probe is connected to the negative terminal. This ensures that the voltage measurement is accurate and corresponds to the polarity of the circuit being tested.

What is negative 48 volt DC voltage?

Negative 48 volt DC voltage is simply a voltage that is negative 48 volts with respect to ground. This voltage is widely used in telecommunication systems.

What is the negative points of using telephone?

There are a great many negative points of using the telephone. These telephone conversations could be tracked and recorded for example.

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