Here is a list of all the postings Norfolk Boy has made in our forums. Click on a thread name to jump to the thread.
|Thread: Upgrading to fibre optic broadband|
I think most people probably understood, so that'll conclude my effort,s let someone more pedantic follow up, I have no further interest and the mods may delete my posts if that helps. Sorry Howard not for you.
Edited By Norfolk Boy on 01/08/2019 18:55:12
"It potentially gets more confusing when ‘milli’ prefixes are used.
Should mB actually be MB? Or perhaps Mb? There are a few orders of 10 between milli and Mega as well as differences between bytes and bits.
A millibyte is one thousandth of a byte not really in general usage unless you into serious geek stuff.
Not sure what to clarify, other than I fell into mB for no other reason than the first letter is a quantative abbreviation and the sceond could be a proper noun, as in kM for kilometre. It could be more properly Mb or MB
I am no expert in this particular area but simplistically, bytes are usually in reference to storage eg a 2 gigabyte hard drive (usually abbr' to 2 gig)
Bits is the transmission of data or bandwidths, If you download 100mb of data in 16 seconds if you had twice the bandwidth you can download it in 8 secs.
A Byte is 8 "bits" as in one character letter "a"
A kilobyte is 1024 bytes as in the binary mathmatical progression 1,2,4,8,16,32,64,128,256,512,1024.
I realise the kilo and 1024 do not equate but in this context it is what it means.
A megabyte is 1,048,576 bytes or 1,024 kilobytes
If I may without giving offence just give a slightly different viewpoint
"Initially when other providers were allowed to compete with BT they made them put in their own equipment at the exchange and rent the space which restricted the availability"
Not true Bt were forced to provide space in their own premises for equipment that the other service provider choose to install.
"To improve competition regulations were changed and now the other providers can rent a block of BT equipment" Other service providers were and have always been able to wholesale from BT and retail on ADSL and VDSL especially in smaller exchanges where it did/does not make economic sense for them to install their own equipment.
"Some of the equipment is now miniaturised and distributed in to the roadside cabinets and the connection to the cabinet from the exchange is fibre optic."
Not quite correct. Whilst there is some condensing of space depending on the type of line card fitted 24 or 32 port it would hardly be referred to as miniturised it is still a DSLAM shelf.
"This used to be deceptively advertised as a fibre service" I agree in part but I don't think it was deceptive more misguided. "Still uses the same wires though which are managed by Openreach. You don't see them stringing a new bit of wire each time someone changes provider." That's what made it economically viable in the short term to supply faster speeds.
"The equipment is the same" No it isn't, The original iteration of ADSL was up to 8mB and went through upgrades to ADSL 2+ to give up to 24mB the emphasis with all ADSL is UP TO but never quite achieving. The new VDSL dslam will give about 110mB at the dslam so the closest people will get 80mB which is the top cap.
"probably less than 3 years old" No the original DSLAMs installed were ECI and some have been in place for at least 6 years" and "probably still BT owned" No Mostly but not exclusively all DSLAMS are owned by Openreach All that happens is some software settings are changed so max rate and contention ratio applied to your line is changed and the billing software changes.
"If you move from wired to fibre to the home the equipment and the 'wire' has to change so that is the big opportunity to really improve. Be aware that FTTP stands for Fibre to the Premises from some suppliers but used to be Fibre to the Pole from BT so you might still get wire for the last stretch."
There seems to be confusion here. It is quite simple an FTTP product is a fibre in to the premises. Now on a new building site if the developer buys into it FTTP is all you will get. But regardless of that the final fibre connection will be into the home and connected internally to a fibre router. Where there is a copper network then aa hybrid arrangement may occour but if the fibre block is at the top of the pole then a fibre or fibre/copper dropwire will be run into the primises and the fibre will once again go into a fibre router but the telephony could be on the copper totally seperately.
Edited By Norfolk Boy on 01/08/2019 16:22:08
|Thread: Chester 836 Milling Machine|
It's really difficult to be subjective about an opinion regarding capabilty as I cannot compare to a full size industrial machine. For me it came at the right price at the right time but there are niggles. But you are comparing two different beasts. For the amount of work I do it's fine, it's accurate and well more than powerful enough unless you intend to really hog material away it should be fine and the VFD will automatically counter any load.
An industrial machine is always going to be more powerful take bigger cuts and be generally made to a better standard. But how much use will a second hand machine have had?
I have a WM20 i assume fan wise you are referring to the motor fan? On the wm20 it is permanently engaged when the machine is on. i can tell you it is not quiet. I have disconnected it on my machine. Always intended to hard switch or thermal switch or timer after running but have never found the motor gets hot enough to worry for what i am doing. Also the inverter fan parameter was set to permanently on i changed mine to 30 second run on after each use.
|Thread: Anyone recognise this optical magnifier|
Thanks for the info. I must admit I have tried a number of ways to look at things with it, and concluded that it is so difficult to use that I will never have a use for it. I have managed up to now with other means of looking closely at things and I have a set of binocular twin optic microscope (don't know what else to call it) that I found at work that I assume were used in very early fibre splicing techniques.
I use them infrequently also to be honest, mostly doubling up with reading glasses gets me by. I am just scratching the surface of decluttering in an attempt to create enough space and ready access to things so I can acheive something without spending all day trying to find things. Wasn't a problem when I was younger I remembered where everything thing was, now I have to see things as I glance around. I do realise this is a drop in the ocean but it turned up in the excercise.
Interesting, I work in communications and do splice optical fibres, but I have only been doing it for the last 20 years with relatively modern equipment with lcds screens etc, and have never done the polishing, seen someone do it once. Now looking at the link below the extra light source needed makes a bit more sense, without that not sure its much use.
Having a bit of a clearout (long way to go) found this item in a drawer. I didn't photo the ends but theres a lens each end. I assume it needs an external light source to get the most out of it. I would be interested in it's purpose. It's made in Germany and I think it may be something to do with photography as I acquired it from my father ..I think.
|Thread: What is this electric clock mechanism|
Hi Simon, I used to run one of these using a GPO clock No 36. To drive the clock mechanism will require quite a bit of current for the oomph needed at 48 Volt. I used a system of a slave relay to protect the master clock movement contacts to drive a nicad on float charge to give the neccessary oomph. Very simple and worked for years. So just saying I would advise as Simon mentions above use the relay. Be aware they are quite noisy aith a noticable clunk every 30 seconds. I presume if you operate the mech yours moves on half a minute?
I sold my clock 36 Mechanism and converted the clock to a quiet german quartz mech. Finding one with the right hands was a fiddle. Alan
P.S just so I don't drive Robert into apoplexy with such heresy, I kept the old drive so it can be restored should anyone wish.
Edited By Norfolk Boy on 07/02/2019 07:46:46
Edited By Norfolk Boy on 07/02/2019 07:49:53
Edited By Norfolk Boy on 07/02/2019 07:52:12
|Thread: Gatwick Drone 'Attack'|
"what does this phrase mean please? not familiar with this bit of English."
I think most readily interpreted as the "visual vernacular" (if such a thing exists) of "give the finger" or the V sign, as in "up yours" I hope that has not offended. Maybe even modern, "Yeah Whatever" then do as you like.
Edited By Norfolk Boy on 09/01/2019 21:15:43
|Thread: Modern efficiency !!!!!!!!!|
I tend to keep my cars I bought one in 2000 and still have it but I also bought a new one 3 years ago with the same idea to keep. I have had a EGR fail at 17,000 miles and I get more than a little peeved when the dealership tries to put the blame on the driver. Oh do you do short journeys? No. Do you sit in a lot of traffic because that's what does it, No I don't sit in traffic and I do drive up to the legal limits but it's hard to thrash an auto. It's a design issue to overcome the regulations. I think I will still have my old 20 year car when this one goes into sensor overload and I am not allowed to diagnose the issue because the dealership has the management system sewn up. My old one I have got a device to access the computer and when I needed to get the SRS light turned off the dealers wanted £70 just to turn off the light I bought the device to do it and other stuff for £50. The world has gone mad and we the consumer have let it.
Rant just started Alan
|Thread: Resiliant or standard metric foot mounted motor?|
My Harrison M250 was a factory 240Volt motor with twin link belt and a weighted flywheel and resilient feet, which shows how much they thought a 240V motor needs damping. I fitted a 3 phase motor no resilience as per Harrison 3 phase spec and matched v belts and the difference was not just noticeable but remarkable. The machine is smooth and quiet. I would have no hesitation in hard mounting the motor if you are going 3 phase VFD. That said if it is the easier option I see no harm in fitting a resilient type of motor.
Edited By Norfolk Boy on 03/12/2018 20:22:43
Edited By Norfolk Boy on 03/12/2018 20:23:12
|Thread: Can anyone identify this press?|
Hah, I can't believe I did not spot the steering rack gearing. I have only recently replaced the rack on my old Volvo and was stripping it down to replace the seals but came across a better one already done. So I have a rack and pinion in my spares/scrap box only 3 feet away. I will try to do it justice and make appropriate accessories as I go along. As I say it does seem to be nicely made.
I think it's possible without stripping it down that the handle shaft is the original helically cut steering column shaft as the angle fits that idea. Won't know unless I pull it apart.
Hi All, I don't know specifically what this is. It looks like it's been designed well, and constructed well, with what seems to me a complicated angled rack on the driven shaft to do the pressing.
I can see what it's ability is with interchangeable cutters and plate but it's fitted with what it came with and I have no other cutters. Looks like it was last used to punch square holes in thin sheet.
The base is 10" x 10" in old money.
|Thread: VFD Choice|
PD072 default is 50 Hz maybe up that to 120Hz
Hi ...again, Not used a Huanyang but did consider them, I seem to remember reading something about them defaulting to 400Hz max speed because they are mostly used to run high speed CNC and 120 Hz min speed. Make sure your frequency parameters are set to more appropriate limits.
Hi, The value of the pot will not make too much difference. As long as you are using Voltage detection not current. There will be 0 Volt one end and 10 Volt the other. The slider will return from 0V to 10V across the sweep range regardless of resistance. anywhere from 1k to 20 k pot should be workable. Even if it's a log pot all that means is you will get a rapid change one end of the travel.
It is far more likely you will find one of your settings will be at 50% or thereabouts somewhere, and only changing across a range 0-5volt and then ignoring the 5-10 volt range .it's not uncommon for factory default to be odd.
Edit just read Martins post sayng the same thing(If the VFD only expects a value in the range 0-5V and the pot has 0-15V across it then after 30% of the pot's movement the VFD is seeing the voltage for full speed. Are there any parameters to change the speed select input voltage?)
Edited By Norfolk Boy on 14/07/2018 10:43:36
|Thread: Inverter Control Query|
This to some extent will depend on the make of the inverter, and/or the model in their range. Enhanced models such as the Mitsubishi E700 SC this can refer to, 720 series single phase or 740 3 phase. The point is the "SC" designation, this is designed to link in to a safety module (some standard ISO thing). For home purposes it is quite simple to use the 2 inputs as a break switch for E stop. (There will be people who wish to argue no doubt) If it is not SC desigantion (relatively recent tech I think) then other options needed.
Yaskawa on their V1000 model also have this, as well as a parameter for "fast stop" programmable to a digital input which also locks out the inverter.
To make them a safety stop they lock out any further possibility of engaging power to the motor, thus you can do without a mains NVR lock out in the home shop and still be in safe practice .
It is also possible to do it with relays that self latch on power start momentary buttons. The safety will cut power to the latched relay and because the safety button phsically latches the relays are unable to reenable. The relays will also give you 3 wire capability with 2 wire programming leaving some inputs free for other purposes like jog.
I would suggest downloading manuals of the inverters you are considering and working through them. Initially it can be a bit daunting until you realise there are only a few key things you need out of all of it.
Hope that helps and not confuses.
|Thread: "Reforming" VFD Capacitors|
The company I work for took it seriously enough to routinely (6 months) cycle all the power supply cards that were in the spares cupboards with the working units and swap to reform the capacitors.
When the accountants started running things rather than engineers they decided sending people out to do this routine was a waste of time. The result was not wholescale exploding capacitors (certainly never heard of it) but given the scale there was an increase in dead on the shelf power units when needed. Enough to reinstate the cylcle routine, If nothing else to identify duff spares early. This equipment was put in in the 1980's and is still working and doesn't have a huge failure rate in service. The degradation of the plastic runners holding the cards has been more of a problem.
When I was at college studying electronics some bright spark put a small electrolytic across the bench power supply. Nothing happened for about 3 minutes...then Crack and the room was full of snow. Amazing how much fluff could come out of something so small.
I have been looking at VFD's recently having just bought a couple for the lathes to convert and I read about the reforming. One instruction said after reforming let it sit as that is the time the oxide layer is then rebuilt.
Also advised by a very helpful supplier that they just put it on a 110Volt supply for a while first and that was broadly across all makes.
Type "abb capacitor reforming guide" in google for advice on their processes.
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