arfur mo Posted June 9, 2008 Share Posted June 9, 2008 your not allowed to use service pipes for return earth paths its as simple as that, unfortunatly most members of the public wouldnt know the difference between a main bond and an equipotential bond (TBH its not even an area I concern myself with for exactly this reason) so if they follow your advice of earthing it to the nearest point with a label they may even be putting 240v though their shiny new towel rail - ouch i beleive that applies to sockets etc. or the bonding would not exist at all, see the modified post as a glitch posted before i was completed. but are you saying a towel rail is not fully earthed to a proper earth point? allowing a possible mis-wire or short in a lights switch could even make it live? modern building anything metal has to be bonded, older buildling bonding was done to and between service pipe's. i might be wrong but the kit concerned is low voltage albeit derived from mains transformers, but that part of the kit is earthed in the normal way. so the extra 'E' earthing is for as stated mainly to discharge static, high voltage spikes caused by induction from lightning and the possibility of high voltage coming in directly from the line from say lightning strikes. also main voltage accidentally appearing on the line going out of the building and walloping an exchange engineer, so i don't see any danger being created by the advice i gave - if it is i'll have to inform the telecom training person i was tought by on the main course, and also the recent refresher courses taken - pdq. regs alan regs alan If you think education is difficult, try being stupid!!!! Link to comment Share on other sites More sharing options...
arfur mo Posted June 9, 2008 Share Posted June 9, 2008 A REFLECTION ON PREVIOUS ADVICE in an earlier post in my advice i referred to mains earth bonding, it has been pointed out to me in the more modern buildings what may seem a good earth bonding is in fact not a true safety earth point. although i have reasonable knowledge i'm not a qualified electrician, so i bow to the greater knowledge. while i beleive the likelihood of receiving any shock by connecting any dialing equipments drain point to an 'incorrect' earth point is extremely low (more risk of choking on a pretsel - so you leave them alone too), mainly due to the enforced safety designs of telecom equipment design which is properly licensed to be connected to the public telephone network, any risk no matter how small should be eliminated where at all possible. so with that in mind, and as referred to in my footer - please consult a qualified electrician for your total safety, BEFORE you connect anything to a potential hazard, and get informed advice affecting your particular premises. be careful and be safe regs alan If you think education is difficult, try being stupid!!!! Link to comment Share on other sites More sharing options...
Lectrician Posted June 10, 2008 Share Posted June 10, 2008 not a good idea running the A & B to the dialer, then using the same cable for returning the 2,3 and 5 wires back to the original master socket as you will likely get echoing of conversation caused by inductance. Thats why they are twisted pairs. If inductance was a real probem, we would all be listening to neighbours conversations, and hell, possibly the majority of a villages! I see no problem with utilising additional pairs in a cable - thats what they are there for I would also leave the term 3 at the NTE - No point taking it upto the panel to simply return it. It is actually the ringer that can imbalance a line. Email : martin@askthetrades.co.uk Link to comment Share on other sites More sharing options...
HoofHearted Posted June 10, 2008 Author Share Posted June 10, 2008 Wow! I just checked back after yesterday and i'm amazed to see the number of replies. One important thing that I hadn't realised the importance of is the earthing situation. Not realising this, I connected the 'E' terminal to the earth connector inside my panel. Fortunately, the panel is 2ft above my electricity meter. So I assume there is a good earth to be had there. As for getting my panel to dial out, this is going to be a more complicated matter. Apparently in order to send an sms, it makes a premium rate connection to an alarm centre from where the message is relayed. This is not covered at all in the supplied documentation. My installation manual says it is described in the 'Engineering Manual' which was not supplied. I've asked my supplier to obtain this for me. So far he hasn't come back to me. But this is diagressing from the point of this thread. If I want to ask about dialling out, i'll start a new thread. Link to comment Share on other sites More sharing options...
arfur mo Posted June 10, 2008 Share Posted June 10, 2008 Thats why they are twisted pairs.If inductance was a real probem, we would all be listening to neighbours conversations, and hell, possibly the majority of a villages! mr BT man would not be happy causing major frowning as it is against their regs, the problem of induction won't always happen but you are sending a voice signal in one direction which is the same signal returned up the same path but very slightly later, that can cause an echo effect so really is not best practice and can't be recommended. if BT are subsequently called out on such a complaint, they will charge the client to correct or disconnect anything wired that way, and they won't worrry about your feelings being hurt either. I see no problem with utilising additional pairs in a cable - thats what they are there for no your mistaken, anything above a 2 pair is there for additional line expansion, as it's less uncommon for homes to have more than one line or service the recent habit is to use 3 or 4 pair cable, but it is also used for repair capacity if a core/s are damaged. I would also leave the term 3 at the NTE - No point taking it upto the panel to simply return it. It is actually the ringer that can imbalance a line. wired as i indicated you would be taking '3' from the voice dialer back to the master as that is where all the other '3's are already wired to so makes sense, so you not retuning it from but taking it from it if you see what i mean, thats if you keep the BT's regs of course. regs alan If you think education is difficult, try being stupid!!!! Link to comment Share on other sites More sharing options...
arfur mo Posted June 10, 2008 Share Posted June 10, 2008 Wow! I just checked back after yesterday and i'm amazed to see the number of replies. One important thing that I hadn't realised the importance of is the earthing situation. Not realising this, I connected the 'E' terminal to the earth connector inside my panel. Fortunately, the panel is 2ft above my electricity meter. So I assume there is a good earth to be had there. As for getting my panel to dial out, this is going to be a more complicated matter. Apparently in order to send an sms, it makes a premium rate connection to an alarm centre from where the message is relayed. This is not covered at all in the supplied documentation. My installation manual says it is described in the 'Engineering Manual' which was not supplied. I've asked my supplier to obtain this for me. So far he hasn't come back to me. But this is diagressing from the point of this thread. If I want to ask about dialling out, i'll start a new thread. if you don't connect that 'E' terminal to a proper earth point, there is a chance a spike could come into your equipment from the line and destroy it. the makers service department having seen it before many times will soon identify what happened from the type of fault created, and so will be unlikely to honour any warranty thereafter. the cost of having the proper advice from a trained qualified electrician is far safer for you and your family in this aspect and in the end likely to be far cheaper than if you don't. self confidence is no match for true competence especially where safety is concerned. regs alan If you think education is difficult, try being stupid!!!! Link to comment Share on other sites More sharing options...
Guest anguscanplay Posted June 10, 2008 Share Posted June 10, 2008 wired as i indicated you would be taking '3' from the voice dialer back to the master as that is where all the other '3's are already wired to so makes sense, so you not retuning it from but taking it from it if you see what i mean, thats if you keep the BT's regs of course.regs alan the O/P`s got broadband - number 3 isnt used to make the line ring, thats dealt with by the ringer circuit within the filter all the third cable will do is unbalance the signal again Link to comment Share on other sites More sharing options...
james.wilson Posted June 10, 2008 Share Posted June 10, 2008 The E connections will help with spike protection but will not prevent all. James securitywarehouse Security Supplies from Security Warehouse Trade Members please contact us for your TSI vetted trade discount. Link to comment Share on other sites More sharing options...
arfur mo Posted June 10, 2008 Share Posted June 10, 2008 the O/P`s got broadband - number 3 isnt used to make the line ring, thats dealt with by the ringer circuit within the filter all the third cable will do is unbalance the signal again for gawd sakes Angus read in conjunction with the earlier post. whacks inthe occasional red care or dual com thinks he knows telecom. terminal '3' is needed for older pulse disconnect equipment (earlier trim phones to name but one) and some modern art deco phones that flash a light when it rings. so keep up son, James your off the naughty chair - Angus your on it, so "Batter Up" as they say in America. regs alan If you think education is difficult, try being stupid!!!! Link to comment Share on other sites More sharing options...
Guest anguscanplay Posted June 10, 2008 Share Posted June 10, 2008 for gawd sakes Angus read in conjunction with the earlier post. whacks inthe occasional red care or dual com thinks he knows telecom.terminal '3' is needed for older pulse disconnect equipment (earlier trim phones to name but one) and some modern art deco phones that flash a light when it rings. so keep up son, James your off the naughty chair - Angus your on it, so "Batter Up" as they say in America. regs alan I really cant imagine the O/P (remember him?) has an old style trim phone and modern phones dont need a ringer when as in this case YOUR ON BROADBAND - the ring is generated from the filter strewth, your comms advice is as bad as your mains - LOL Link to comment Share on other sites More sharing options...
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