Here is a list of all the postings Nathan Sharpe has made in our forums. Click on a thread name to jump to the thread.
|Thread: Cubital tunnel sydrome or ulna nerve entrapment|
I've had it for about 20 years. When I attended my hospital referral I had the electrical tests to determine the area before seeing the surgeon . After having the risks of A) severing the nerve- 20%, B) causing further non nerve problems like loss of elbow mobility - 20% , C) partial cure- 35%, I decided not to go ahead with the operation. My numbness changes depending on both useage and temperature, leaning on my elbow makes it worse and being hit on the "funny bone" is not funny ! I can still play guitar and form chords/select notes/pull off etc but with reduced strength , I'm right handed and my problem is my left ulna nerve. Keep it warm, try exercise and use NSAIDs such as Ibuprophen and try not to use the arm rest when driving. In the workshop I have very few problems with it. Nathan. PS. if you have or have had heart probs and you are taking long term medication, check with your GP before self medicating with NSAIDs.
|Thread: Making work equipment.|
Joshua, yes these were large bore suction hoses up to 6" dia . For the 12" and 24" hoses the Bendix units were doubled up . We used to check the pump "suction" with a vacuum gauge fitted to a drilled through nrv ball of the correct diameter, pumps were deemed ok for hire at 20/25 ft vac. Nathan.
|Thread: Tools you Treasure|
Clogs , I know what that feels like. My old man left it all to my half sisters father (house included) to look after his daughter after my Dad died. My old man raised her as his own after mother died . Her father put her in "care" and sold it all , went on the p--s and forgot about her. We , all three children, knew nothing about varying parentage until 1996 when we met up for the first time in 25 years when she noted a difference. When our mother died my (full) sister and I went into"care" because of fathers age , youngest (half) sister remained with her father (living with us) and my father. When she found out she went on the "p--s" also , on his grave. Nathan.
|Thread: Making work equipment.|
To the best of my knowledge Godwin pumps used (and probably still do if Godwins still exist) a venturi air extraction/vaccum pump on their engine driven centrifugal pumps to evacuate air within suction pipework. This was driven by a standard Bendix 2cyl compressor into a jet at 90 deg from a similar jet on the suction hose side , the air was ejected via a shaped nozzle at 90 deg from the suction nozzle. These were not CE marked as an individual component/system (circa 2003 ) but CE compliance may have been due to the whole pumpset being CE compliant. If I remember correctly all items were standard Bendix part no's. We had a leachate Eductor system as part of the hire fleet (SLD pumps) which used the same system. Nathan.
|Thread: Continuous use of a phase convertor.|
Evening all. Mark, I wish we could go that way but the cost would be prohibitive! Like Muzzer ,I prefer one VFD/machine. I do normally have to share the control circuit via a "flip/flop" or switching relay and yes all circuits are debounced. The currently faulty inverter has been sent back to the manufacturer for testing and repair/full report. We will continue to support this manufacturer because of their support system. The system is working as designed but on one pump. We have asked another of our suppliers if they could supply a standard panel with phase conversion built in and their answer was "We do it all the time " , so a site visit has been arranged and I will await their design with bated breath ! They tell us that their solution fits within an existing panel (Theirs) alongside of the standard control gear, I will report back to you all if this is something which could be a legit solution for my problem and,I suspect, many problems suffered by others on here who need a non inverter 3ph supply. Nathan.
An edit to my previous post. We design and install inverter driven water pumping stations where I can give more info via pressure/flow/level sensors to the inverter to prepare it for a start and to allow it to monitor these parameters and therefore deal with them before a sensor driven stop. With sewage being pumped into a" public" sewer we are pumping into an open ended pipe so we do not have the gradual increase in pressure to work with, flowmeters cease to read even with Magflow units and ultrasonic level controls are thrown into disarray because of the very "splashy" flow into most private sewage wet wells. We rely on float switches, a coarse on/off action, which could happen and does happen to the upper float quite a few times before a positive on switching is achieved. We do loads of sewage work ( the majority of our work) but prefer a standard DOL/Star Delta system for both single and three phase stations. This particular job has no 3ph supply available but my boss has specified 3ph pumps to the client. Nathan.
Thank you all for your input. The inverters we are using ( Invertek Optidrive e3) are correctly configured and we are using our control circuit on the correct IP/OP terminals. They are British made and have a specific parameter set for pumps. My question was answered by both Martin P and Scrumpy after that I lost interest. I did ask that you did not tell me about inverters, I know about inverters, we install 35/40 inverter driven systems each year but they have not been reliable or effective on this job and I need to find another way to power these sewage pumps before the ground floor flats start to flood AGAIN! Nathan.
Thank you Martin P and Scrumpy. That is the exact application I have in mind . We need to power a 3ph pump control panel running 2 sub pumps from a single phase supply . We currently have two single phase in three phase out (230v) inverters trying to do the job and they do work after a fashion but are unreliable so far. It looks like they do not like too many switching operations instigated by the float switches and they also add a level of complexity that I do not like on what should be a simple system ! Nathan.
Thanks vintagengineer, but what I'm looking for is a knowledge from a source which is non manufacturer but IS from someone who has knowledge of this through work or self use. I have had enough of the "advice" from sales orientated tech departments. I need advice from real working humans. Nathan.
Can a phase converter, not a VFD/Inverter, be run continuously ? It would be powered and in ready mode most of the time and in use (on demand by the load) two to four times a day. Please do not tell me about VFD's/ Inverter's . They are not suited to the possible application and we have already tried them. We do not have 3ph supply available, do have dual voltage motors and have reconfigured to 220/230 v 3ph . My workshop is run from a Transwave converter and has been for 20 years without any hassle but it is a home/hobby workshop and not an everyday continuous use application. I need to know if I can run a 24 hour/7 day/52 week system on a converter. Can any of you help? Nathan.
|Thread: Armoured cable - what size would you reccomend|
I was taught that SWA armour was to be used as an equipotential bonding conductor and should be connected to the circuit protective earth. The Reg's still state this. On periodic inspection testing the continuity of Bonding, Circuit Protective Earth and Phase Conductors is carried out on individual cores/wire armour to make sure that all potential current paths are proved to be ,A) continuous, and B) meet minimum insulation resistance requirements. This will show up any existing and any potential faults with the cable if the IR is less 1.5megohm. The Reg's state that while a circuit showing IR of 1.5 megohm is acceptable further investigation should be undertaken to find any latent faults within the circuit. Nathan.
|Thread: Anybody know what these are ?|
What stoopid puts left hand threads on wheel nuts?
Would that be similar to those as buys LDV?
|Thread: What Did You Do Today (2017)|
Murray, can I suggest that you look at Effast pvc? A short radius 110mm/4" elbow with two short stubs of pipe, multiquick on the pan and possibly another to the soil pipe socket ( if the effast pvc will not fit) should do the job. There are other( cheaper) pvc fittings available, these are simply the range we use at work and are at least 10 bar rated ( if you fully seal the pan when using / had a mega curry last night that could be useful!), and are easily available but are costly. Wall thickness is can be machined to suit your soil pipe by yourself. Nathan
|Thread: TEC Strange wires|
In my line of work they are commonly known as Klixon connections, a thermally operated switch, which if you have the terminations for ( on your control panel) you should connect. It can save from a few hundred to many thousands of pounds sterling in downtime/rewinds on pumps (my line of work) or conversely cost YOU that much! I'm not sure who, of the pump manufacturers, made them popular but it was probably Flygt. Nathan.
|Thread: What is this for please?|
Looks like a pump of some kind, possibly double acting unless the piston has a non return valve built in to allow single acting. Nathan.
|Thread: Myford headstock bearing replacement|
I'm glad I bought a Harrison! 25 yrs in my ownership and none of this sort of faffing about. Nathan.
|Thread: Opening .rfa files|
Thanks Robbo but that is RFA which is a gaming file. I need .rfa to open a BIM file from heatrae sadia to read the spec and installation instructions for their Megaflow water heaters. Nathan.
|Thread: NZ Quake|
What's the time difference between UK and NZ ? Ian SC was on at 08.32 forum time. Nathan
|Thread: Opening .rfa files|
I need to open a few files with the extension .rfa which is I think an Autodesk extension. I've been to the Autodesk site to try and download a trial but no trial is available for my operating system. I'm running Win 10 32bit. Any advice (apart from changing the OS!) would be welcome. Nathan.
|Thread: What Did You Do Today (2016)|
Which version Neil? For the Kingsmen I can get away with Am/D/Em/C (on Guitar) for a suitably amateur sound ! Nathan.
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