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Analog phone lines, at least in North America, do have polarity, or a difference between positive and negative. "On-hook" dial tone current is about 48 volts DC. North American wiring calls for a minimum of two wires (red & green), though a second pair (black and yellow) is probably present. For voice use, phone line polarity doesn't really matter; it will work either way. However, computer modems, fax machines, alarm systems, etc. may not work at all if the phone line's polarity is reversed. Or they may work, but their performance is degraded. The red wire is the "ring" or negative wire. The green wire is the "tip" or positive wire.
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Can reverse polarity burn a tv set?
If, by 'reverse polarity', you mean the accidental reversal of the line and neutral conductors at the socket outlet or receptacle, then the answer is no.
What is axis of polarity?
The axis of polarity is the imaginary line that runs through the earth from one pole to another. The earth does not have a strictly vertical axis. The earth rotates on a tilt.
How do you Hookup laptop to regular phone line?
Plug the phone line into the phone line receptacle in the back.
What do you mean by land line and cellular phone?
A land line is a house phone, that must be attached to a phone line or a device connected to a phone line. A cellular phone is a mobile phone that allows you to move freely anywhere.
What is used to check for line voltage sags?
just a digital voltage meter measure at the origin, and then at the end of line
How can you do the polarity test of a switch?
A 'polarity test', as it applies to a switch, is performed to confirm that the switch is located in the line conductor and not in the neutral conductor.
Does a single-line phone set mean there is only one phone number or only one phone on the line?
A single line phone set means the phone itself can only handle 1 line connected to it. No multiplele lines on a single line phone set. :(
Can you keep your land phone line number if you get a cell phone?
Yes you can. Your phone line has nothing too do with your cell phone. In fact, for most people your phone line carrier is completely different from your cell phone carrier. And you phone line has absoloute no connection TO YOU HOME PHONE AT all
What is needed to convert a 1 line phone system into a 2 line phone system?
To convert a 1 line phone system into a 2 line phone system you will need a phone that has two input jacks and two separate phone lines coming into the building. Each phone line will be plugged into one of the input jacks and the phone will then be able to receive calls on either line.
Differentiate between normal and reverse polarity?
It depends on the context. In a.c. circuits, 'reverse polarity' describes a situation in which a device, such as a socket outlet, is wrongly wired -with the line and neutral conductors interchanged.
What is the use of polarity test?
I will assume that your question is in reference to CT and transformer polarity.In the case of a CT (Current Transformer) they have to be installed in the correct direction for proper metering. The polarity check is used to verify that they are installed correctly and that the polarity marks are correct (if the CT has them).In the case of a transformer there are two types of polarity, additive and subtractive. If you are paralleling transformers you have to ensure that they are the same type polarity in addition to other attributes.Hope this helps.Alternative AnswerIn a new electrical installation, a polarity test is conducted to ensure that socket outlet terminals are correctly wired (line really is line, neutral really is neutral, and the protective conductor (earth/ground) really is protective conductor. It's also important, for example, that the centre pin on an Edison Screw lampholder is connected to line, and not to neutral.
How do you use a fax machine from house phone?
You connect the fax machine to the phone line - the same type of phone line that the phone is connected to. If you want to use the same phone jack, you may need to either get a phone line splitter, or some phones have an "extension" so that another line can be added to a phone.
