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In telecommunications and professional audio, a balanced line or balanced signal pair is a circuit consisting of two conductors of the same type, each of which have equal impedances along their lengths and equal impedances to ground and to other circuits. The chief advantage of the balanced line format is good rejection of common-mode noise and interference when fed to a differential device such as a transformer or differential amplifier. Common forms of balanced line are twin-lead, used for radio frequency signals and twisted pair, used for lower frequencies. They are to be contrasted to unbalanced lines, such as coaxial cable, which is designed to have its return conductor connected to ground, or circuits whose return conductor actually is ground (see earth-return telegraph). Balanced and unbalanced circuits can be interfaced using a device called a balun.
Circuits driving balanced lines must themselves be balanced to maintain the benefits of balance. This may be achieved by transformer coupling (repeating coils) or by merely balancing the impedance in each conductor.
Lines carrying symmetric signals (those with equal amplitudes but opposite polarities on each leg) are often incorrectly referred to as "balanced", but this is actually differential signaling. Balanced lines and differential signaling are often used together, but they are not the same thing. Differential signaling does not make a line balanced, nor does noise rejection in balanced cables require differential signaling.

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  1. S

    Balanced compartment boilerhouse

    Hi, I have a balanced compartment boiler house, fitted with 3 forced draught open flued boilers, is this acceptable? Don't have access to ige/up/10 to double check, and the literature I do have is very light on the subject. Thank you.
  2. S

    Balanced compartment.

    Hi, I have a balanced compartment boilerhouse, with 3 force draught open flue boilers, is this OK? I don't have access to ige/up/10.
  3. P

    Cylinder noise / Balanced Colds / Pressure etc

    I wanted to start a new more dedicated thread as I am on about 3 just now in one way or another trying to get up to speed with my problem. The issue is that my Gledhill Stainless Lite indirect unvented cylinder makes loud noises when heating - this is a bit random, but that noise is loud enough...
  4. V

    I Balanced My System But Now Have High Pressure

    Hi everyone this is my first post - I have no idea what I'm doing with plumbing and heating - have had some success by reading forums etc but now I'm stuck. I live in a townhouse with 3 floors. Never had much heat in radiators on my ground or 3rd floor. So I rebalanced the system. (Put all...
  5. J

    Retro-fitting balanced cold on an unvented - query

    Hi all, fairly new to G3 work as recently certified (!). Done a couple of installs from scratch, all good. Job here is to retro-fit a balanced cold circuit from a Gledhill unvented to a recently refurbed bathroom that now has all mixers (apart obviously the toilet). Cylinder has Reliance...
  6. D

    URGENT want to fit tmv2 but supples to basin taps not balanced pressures

    have gravity hot, mains cold to basin taps,require to fit a tmv2 anything i can fit to avoid trying to get gravity cold to taps to balance
  7. MikeJhn

    Spare part for an old balanced flue boiler

    Guys Modification of any fuel burning appliance is strictly forbidden unless you have the approval from the original manufacturer If you want more efficient boiler change it don’t start modifying your existing one

    Power flue to Balanced flue

    Further to my post earlier today, a change of plan. Is it possible to change a power flue fire with no chimney to a Balanced flue fire? and if so, what is involved
  9. P

    Must balanced flue inner and outer be the same length?

    Hi. Our builders hit a problem with extending the balanced flue through a new extension. Their solution was to have the outer, intake pipe terminate at an external wall, but add an extra section to the inner pipe to take the exhaust away from the next house. However, the gas boiler was...
  10. S

    Heatslave 26 32 RS Balanced Vertical Flue

    Hi Folks, I'm trying to track down a Heatslave 26 32 vertical balanced flue to replace/extend our existing horizontal flue. I have a local engineer who is happy to do the work but didn't want to do the leg work finding a flue which is no longer made. I'm waiting to hear from Worcester Bosch...
  11. T

    Balanced Cold water - Megaflo

    Hi There, I've just had my heating system fitted and wanted to know where the balanced cold should have been fitted as I've been reading the manual and it says it should be straight after the 3 bar reducing valve. Looking at way he did mine was after the 8 Bar pressure Relief Valve and then...
  12. H

    Oil Rayburn 480 kb balanced flue high CO

    Any advice much Appreiciated. I was called to Rayburn 480kb its Eco Flam >2001 customer complaining about fumes smell lock out. I Serviced and set up as below after Striping cooker burner and adjusted setting No signs of damage in chamber replaced new burner seals flue readings i now set to...
  13. K

    Supply to unvented cylinder

    Hi all, I currently have a 15mm mains supply to a unvented cylinder in the loft as the pipe goes under a tiled floor en suite and it was not upgraded during the installation. I am now in a position to upgrade to 22mm but do I have to use a G3 qualified plumber for renewing the 15mm to 22mm...
  14. 2

    Pipe query

    Long time reader, 1st time poster. So I'm planning to change some pipes before I re-do bathroom and decorate the bedroom above it. I plan on running 22mm and branching off 15mm to kitchen and other taps. What I am unsure about is weather to have a 22mm branch to the bath and shower before any...
  15. M

    Worcester Bosch Oil Combi Heatslave 26/32 replacement

    Our 14 year old WB Oil Fired combi has sprung a leak, engineer says either in the Heatslave tank or the boiler tank. He says it's not worth repairing. There's an unused 26/32 for sale on ebay at the moment. Our model has a conventional flue, with silencer kit fitted. The flue exits straight...
  16. A

    detach the snorkel on a balanced flue

    Hi chaps, Bit of a bugger today - warm flow Utility 150HE , situated in a garage with a balanced low level flue It has gone sooty so cleaned it up changed nozz etc etc but when doing the flue gas analysis , no matter how much I opened up the air intake I could not get enough air. `the only way...
  17. T

    Mounting a combi after a balanced flue

    What do people generally prefer to do in this situation. Old boiler with square flue off the wall and new boiler in same place. Do you use a non combustible board or block up with rapid set cement or any other tricks I don't know about. thanks
  18. B

    Grant flexible balanced flue - anyone fitted one?

    Ive priced to fit a new boiler using one of these kits. Its a 6 metre chimney which Ill be accessing of a large pogo stick. ANy advice? :-)
  19. M

    Oil boiler with flexible balanced flue

    I've got a job coming up to fit an oil boiler in a utility. It's replacing an old boiler flueing into a lined chimney. The boiler is sited so I can't fit either a horizontal flue (even with plume management) or vertical. They're reluctant to move the boiler, or change to an external one. I'm...
  20. F

    Balanced feeds

    Morning, I have two questions.... I presume that taking a toilet cistern feed of the balanced cold is fine and itdoesn’t need to be run back and connected before the PRV? On a kitchen sink we have a mixer - Can we run a cold feed pre the softener, andfit 1 2bar PRV so that it matched the...