Smart Electrics Posted July 28, 2005 Posted July 28, 2005 I would say its the bell box NICAD that has started playing up. possibly has either leaked onto the PCP board and the copper sulphate is causing problems aswell as a damaged batt.
Mavrick_001 Posted July 29, 2005 Posted July 29, 2005 As an A class licence holder and a well respected engineer the RFI problem is valid. I've been to a few wired systems where the fault has been traced to taxi companys transceivers causing tamper problems and the odd detector fault. Just for you SPARKy I'll explain so next time you don't put a new bellbox up... tell em problem solved and then for the upset customer comming on here to say he wants the system disconnecting because he's had 2 engineers out who can't fix it. Anything conductive of length will act as an antenna, the lenght of the conductor will determin it's resinant frequency.... a determined lenght will be sepcific to an individual frequency..., this frequency will then have harmonics which are 2* the resinat frequency, 3&, 4* and so on, basically multiples of the res frequency. With me so far.... I know your a spark an all (use to be one before I became just too good!!)... right keep up... An alarm cable in an installation will have a fixed length, this alarm cable will act as an antenna... because it is conductive.... it's lenght will determin it's exact resinat frequency and all multiple harmonic frequencies.... if it hapens to be nearby a transmitter which has enough rf power on the resinat frequency or the harmonics of this it can cause the alarm panel to go into alarm. I personally have a gardtec 840 installed... earlier version where they relied on chrystals to control the timebase or system clock as it's sometimes refered to. These chrystals have a frequency as all do.... however the happen to be in the 3mhz band which is near by a ham frequency.... possibly one cause... however, when I use 80watts + rf power from my transceiver my alarm throws up tampers on the data line mainly such as zex expanders, keypad tamper etc etc, my alarm cables will have a resinant frequency, they will pick up my electromagnetic waves (rf... radio frequency for spark who thinks lol in his reply) and trigger off the alarm. This is with 80w & I'm licenced to use 400w and can get permission to use upto 1000w then you see that the point is valid. But then again I don't know what I'm talking about.... as I only have test equipment to frequency sniff and find the frequency causing the problem, only a meter which I can put on the end of the alarm cables to find out there reinant frequency and seeings that I cqan sort it out.. I must be talking rubbish.... oh just one thing, ask dave from ACT meters why he bothers making rfi filters and ask him what a ferrite ring is..... But then again tell me I'm talking rubbish.... yesterday I've only unlocked to gardtec 800 series (800&816) locked engineer codes, gardtec says that engineers can't do it and that it needs to be returned for a new chip... umm I do 2 in a day and tech support don't even know how to do it.... sorry the guy with the problem with his system.... go and waste some money with sparky and have a new bellbox.... give me a call if it doesn't work so I can have a laugh!!! It might be the bell, pcb on panel... it seems strange that you've linked it out and the fault is still there. Transmitting antennas are not always visable, I personally have a wire antenna run horizontal 50ft long and at 10meters away you can't see the thing.... good luck!!! CCTV Intruder Access Control Tony Hughes, Proprietor, TRADE MEMBER
Guest chumbawumba Posted July 30, 2005 Posted July 30, 2005 Hi All. I have no idea what bellbox it is. It's an old one, and being on the side of a detaced house, and very high up, it is very inaccessible. The terminal I isolated was the "TAMP" circuit and not the connector marked "BELL". would also isolating the BELL circuit prevent the alarm going off, if indeed the bell is faulty? I'm pretty sure the actual panel lid isnt faulty because gently pushing and banging it doesnt cause a tamper. The RFI suggestion is interesting. No other alarms go off in the road, but perhaps theirs are less susceptible to this form of interference. To be honest i'd like to disable the alarm altogether. I can understand that such information wouldn't be given in a public forum. (Mavrick_001: I am based in frodsham, which is between chester and warrington.)
Service Engineer Posted July 30, 2005 Posted July 30, 2005 As an A class licence holder and a well respected engineer the RFI problem is valid.Ditto and Agreed.yesterday I've only unlocked to gardtec 800 series (800&816) locked engineer codes, gardtec says that engineers can't do it and that it needs to be returned for a new chipI need to know how, please PM me details. ........................................................ Dave Partridge (Romec Service Engineer)
Mavrick_001 Posted July 30, 2005 Posted July 30, 2005 Frodsham is a good drive for me but have worked up there a few times... there is is cct in the panel for the bell tamper.... however if the fault is at the bell side of things then it needs to be got upto.... will a set of tripple ladders do the trick??? Qustion is really do you want to spend anything on sorting the system out or do you just want to disconnect the lot?? If you let us know what your current thoughts are I'll pm you with deatils of contacting me if required, regards Mav.... Dave.. top secret pm on the way... CCTV Intruder Access Control Tony Hughes, Proprietor, TRADE MEMBER
sparky83 Posted July 30, 2005 Posted July 30, 2005 Well you are entitled to your view but I've never come across a fault like that before! I see where you are coming from but I thought it might be some speil you've dreamed up to confuse the customer! I just thought its more likely to be the bell which it sounds like it is! For your information I'm not an electrican I'm just called Mark, I'm only 22 so excuse my nievety however I have got my NVQ level III in alarm installations not that it means a lot! We've had prolems with RFI setting motion detectors off but never tampers but I agree that maybe in a data line you might. Trade Member
Mavrick_001 Posted July 30, 2005 Posted July 30, 2005 Well Mark... 1st of all I don't dream up rubbish on here to confuse customers to rip them off and make money. Secondly in this trade you'll always find someone who knows a little more than you and I'm still finding out that others still know more than me... and after having years of experience in the trade and having a vast amount of technical knowledge I'm not trying to make anyone look like a prat but the lol didn't go down well and as your now probabally awear with an nvq level III you've still got a lot to learn.... as well all probabally have. In future take on board what others are saying and look into their view 1st before making any quick responses. As you can see the customer has given us some more information whichs point to the sab being at fault but you can't say hand on heart that is the fault without going to the system, if your not at the system you should never assume a fault as you could be batting in the wrong direction, all options should be considered and you should look at every job/fault as a blank page. CCTV Intruder Access Control Tony Hughes, Proprietor, TRADE MEMBER
whistle Posted July 30, 2005 Posted July 30, 2005 Bell ringing when unset with tamper fault i would be 95% its a sab fault test the bell cable replace the bellbox and check the batt in the panel is ok. i am sure you will have no more problems.
whistle Posted July 30, 2005 Posted July 30, 2005 try disconnecting all the bell wires from the panel link out the tamper and give it a week. If the sab kicks in get out your ladders and dis the nicad or flash the sab with 240v LOL only joking but i must say i have done it more than once on a rip out in a town centre when the car is miles away with the ladders on. You down power the panel and the sab kicks in. NOT RECOMENDED
Nova-Security Posted July 30, 2005 Posted July 30, 2005 As an A class licence holder and a well respected engineer the RFI problem is valid. Transmitting antennas are not always visable, I personally have a wire antenna run horizontal 50ft long and at 10meters away you can't see the thing.... good luck!!! 62807[/snapback] What is being said here, is basically wrap you bell box in tin foil to stop any RF interference you dont know whats around. Mavrick, tried anything on 10Ghz www.nova-security.co.uk www.nsiapproved.co.uk No PMs please unless i know you or you are using this board with your proper name.
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