Member postings for Martin Newbold

Why does the inverter go 100hz. i presume it is driving it twice as fast then, and over driving it perhaps there is a limiter in inverter to stop this i will look.

I have a 7" pulley d2 and a four way pulley on lowest pulley is driving the 7" picador pulley. This rotates a shaft with a 5" pulley on it driving the lathes 5" pulley

aha it sinks in the cone pulley drive is RDGTOOLS 4 STEP VEE PULLEY 24MM BORE 2" 3" 4" 5" DIAMETER A SECTION PULLEY , which is 2" not 1"

This is why its driving 805.71 lol

the inverter shows 50hz at 800rpm but my HS2234 digital tachometer is temperamental it usually gives you one acurate measurement before it gets confussed a battery reset removal usually works . 542 rpm is shown on inverter at 1 amp motor rpm is set and  moror is rated at 5.5 / 3.0  amp

M

Edited By Martin Newbold on 30/08/2017 19:43:31

I have been using Pulley and RPM Calculator at www.culvermotor.com/Engineering-Formulous/Pulley-and-RPM-Calculator.html

I used my rpm final speed of 2820rpm with Diameter1 of 1 and Diameter2 as 7 representing pulley sizes in inches. This gave 402.86rpm .My final pulleys are same size. Now I would expect my inverter at 50% to run half this and 100% run 402.86rpm . I bought a simple light rpm detector and amazingly at 50% the rpm is 800rpm. Can anyone help or explain what is wrong here please?

M

Edited By Martin Newbold on 30/08/2017 18:36:29

You said you cant locate a switch mode supply have you tried RS Electronics

Hi All, I have got it running with the help of Mike Pool it reverses through Dewhurst coreectly and is looking good . I have to bolt it in and get a new pulley as bore of shaft is larger at 24mm. Curiously the Motorrun Phase converter occasionally trips the shed fuse instead of the house fuse which is unlike the VFD I had.

I have worked out this seems to be to do with the order it is switched on. I am happy the motor I have chosen is larger and more capable that the pathetic power motors I have been advised previously by suppliers to buy. Things are starting to come togethr finally to get it working.

Edited By Martin Newbold on 22/08/2017 09:54:05

Hi 'not done it yet' I dont have a VFD As lost confidence with these devices and wanted something that would work , Its running of this MotoRun Phase converter through a Dewhurst Reversing switch currently. You need to check the engine plate for what the motor will run they are all differant. Its quite a challange. Having built a gear box I can alter speed here by changing pulleys and didnt think the VFD I had used gave power though out the range of speeds. Thanks

Thanks for your help its seems to be working. So have left it alone till i get some more paint.

Brian is this configured in star . If i understand you correct I need toconnect a b &  c to U1  W1 V1 does it matter in which order?

Edited By Martin Newbold on 21/08/2017 19:13:07

I just looked at the connections again as gave you duff information in need 415 volt

I have connected as default

W2--------U2---------V2

U1           W1            V1

Edited By Martin Newbold on 21/08/2017 19:02:57

Edited By Martin Newbold on 21/08/2017 19:04:51

Thanks Mike yes been having some problems retrieving it from my network printer the location of the memory cards seems to change weekly

I am sure this is siple but just dont want to blow up a second motor, As you see it has V1 V2 and V2 have been told its connected in DELTA

Motor plate is below

Edited By Martin Newbold on 21/08/2017 18:43:04

What am trying to find out is what is A B and C as in Data sheet for type A reversing switch for Dewhurst SDR52 switch are connecting to in motor but have no data sheet for motor.

Does anyone one have an instruction sheet for GEC size D90S No LA303 1.5 KW , please?

Hi Larry . Its sitting on Marine ply on 4x2 frame under shed on concrete base.

You wrote "Surprised that it,s quieter on a wooden floor,I would have thought it would be more noisy. I had half the frame fitted with a chipboard shelf and it seemed to act as a sounding board. The only reason I did not leave it on the floor was to use that space for other stuff. I will see about fitting rubber buffers to it,but I dont want it bouncing all over the place. If it fell off the shelf,it would make bits of itself,and me,if I was near enough ! I think most of the noise comes from the steel box holding the bits and pieces,because if I press my hands to the top of it,the vibrations reduce,and likewise the noise.

It,s not that bad but just something one could do without,the machines make enough noise themselves."

But having said all that,they do work,and that,s what matters because out in the sticks there is no way to get 3ph."

Edited By Martin Newbold on 18/08/2017 17:07:44

Mine is possibly more quiet as its on wooden floor. You could try a wooden shelf on top of your metal frame.

Just a thought if you making the model from a 3d printer why not use it as a former for a sand mould and use aluminum melted to create the new part. There are lots of videos on Youtube to look at

Aluminium melts at a low temperature. There is some science here and three ways of melting it **LINK** I would imagine there are far more better people on here to advise about casting process but this is what i would look at with your 3d former. Aluminium is quite easy to shape too with a file. You could also look at brass instead of aluminum. The tape wrapped around it was initially i expect to stop the aluminum transferring to the user.

M

Edited By Martin Newbold on 17/08/2017 14:24:45

Am waiting for my newest adventure in a motor to turn up . Have my fingers crossed with this one

Thank you so much Clive, Yes the circuit diagram shows a 3 phase connection on the type A Dewhurst (**LINK**). I am guessing that I need to isolate the single and three phase earths and this is what is most likley causing the the fuse box to trip as when I unplug single phase equipment the converter runs fine and has a big clunk as it switches on

This is a bit odd I think i need pdf . When i connect yellow and green to earth and any phases to Dewhurst switch 1 , 3,4 it blows my trip in the fuse box any ideas please have disconnected it all tonight for safety.

oh middle one was 1/2hp to 1hp lol You said i need to connect the wires in specific initial phase series I am connecting to 1, 3 & 4 on dewhurst

HI Clive,

Yes this has Punch and Start on one toggle and three positions on the other toggles switch 2.5h to 4hp, 1/2 to 1hp and 1/2 to 2 1/2hp

I have tried to message you but your profiles is private.