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Member postings for Les Jones 1

Here is a list of all the postings Les Jones 1 has made in our forums. Click on a thread name to jump to the thread.

Thread: Wiring a VFD to a foot switch?
13/01/2023 14:26:36

Looking at the information in the advert for the VFD I can't decide if there are two different versions of the VFD or the same version can be used with either three phase or single phase motor. The picture with a singe phase motor seems to connect the main winding to one phase and the start winding to another phase. (I assume that the capacitor that is normally in series with the start winding is removed.) Can you post the manual for the VFD so we can see if any configuration settings need to be changed.

Les.

Thread: Some VERY interesting LED modules
12/01/2023 18:25:30

Ian makes a good point as beginners may be tempted to drive them with a constant voltage rather than a constant current. As well as the voltage for a given current changing with temperature it can be different between samples of LEDs. This is why it is a bad idea to drive LEDs in parallel. (Unless they are matched.)

Les.

12/01/2023 17:29:12

The two that I ordered arrived today. I found a suitable heatsink to use.

img_1868.jpg

Here are some measurements of voltage against current

100 mA 40.24 V
200 mA 41.21 V
300 mA 42.07 V
400 mA 42.80 V
500 mA 43.29 V
600 mA 43.76 V
700 mA 44.15 V

Even at 100 mA it was quite bright.
Many thanks to Michael for pointing them out.

Les.

Thread: Drill Press Run out
12/01/2023 08:58:22

Andrew has still not specified the units of his 0.03 so we still do not know just how bad it is.

Les.

Thread: Can i reverse this motor ?
23/12/2022 22:26:27

I SUSPECT that swapping over the blue wire that comes from the top middle terminal to the top left terminal with the brown wire that comes from the top right terminal to the bottom left terminal will reverse the motor. DO NOT try this without verifying that my assumptions are correct.
1 Verify that the centrifugal switch is connected between the top right and bottom right terminals

2 Verify that the main winding is connected between top middle terminal and the bottom left terminal

3 Verify that the start winding is connected between top left terminal and the bottom middle terminal.

Les.

Thread: Weller soldering iron bits
07/12/2022 22:17:13

Andrew, In your first post you say " I have a couple of spare barrels (which define the temperature ". If this is the case then it does not use the curie effect. The Weller tips that use the curie effect have a small piece of metal on the back end of the bit. It is the curie point temperature that defines the temperature. There is a small magnet attached to a microswitch. When the metal on the back of the tip is below it's curie point the magnet is attracted to it switching on the heater. When the temperature is above the curie point the magnet is no longer attracted to it so the heater is switched off. On the Weller tips that I have a number is stamped onto the piece of metal to show the operating temperature of the bit. (The ones I have are marked with a 6 or a 7.) The model of the Weller iron that I have is a TCP1. This is marked on the metal flange that is fixed to the handle.

Les.

Thread: Replacement 1ph motor wiring (Warco BH600)
20/11/2022 16:03:03

In your post on 19/11/22 at 20:00 You do not say how you have wired the motor. If I assume that you wired it as you described in your first post with wire V2 connected to Z2W2 then I think the problem is with K2 or K3. One of the should pull in for forward and one for reverse. Does this happen ? If it does then the problem is likely to be one (Or more) of the contact sets on that contactor. If neither of these contactors pulls in for reverse Then we need to look at the control wiring feeding the coil on this contactor.

Les.

20/11/2022 10:12:04

Looking at your diagram in the first post this is how I think the motor is wired internally.

U1 to U2 is the main winding.

The auxiliary winding is between Z2W2 and the point where the two capacitors are connected together..(Yellow wire to the inside of the motor.

The centrifugal switch is connected between V1 and the side of the 150 uF capacitor with the black wire connected to it.

You can confirm if I am correct by doing the following resistance tests.

1 / measure the resistance between the black wire connected to the 150 uf capacitor and V1. This reading should be very close to zero ohms.

2 / Measure the resistance between U1 and U2. this should be quite a low resistance. (Less than 20 ohms,)

3 / Measure the resistance between Z2W2 and the red wire between the two capacitors.This reading should be quite low but a a bit higher in the reading from test 2

4 / measure the resistance between U1 and Z2W2 This should be a very high resistance probably more than 20 Meg ohms which is probably higher than you meter is capable of reading.

If these readings confirm my theory then connect the output from the reversing switch whose polarity is the same in forward and reverse to U1 and U2

Connect the output from the reversing switch whose polarity is reversed between the forward and and reverse positions of the switch to V1 and Z2W2.

Les.

Thread: Accessories for NHS Hearing Aids?
18/10/2022 20:58:29

I suspect the device creates an induction loop. This is just a loop of wire driven from a low impedance audio amplifier. The loop could be round the perimeter of the room or just a loop close to the hearing aids. It could also be some kind of RF link.I did try making an induction loop that I hung around my neck. It worked but i found it better just to use wireless headphones. (I would avoid Bluetooth wireless headphones as they give a slight delay on the sound.)

Les.

Thread: Chester DB8 Timing Belt
15/09/2022 15:56:33

If the DB8 is similar to the DB-10G then I think the idler (The large toothed belt pulley and the stepped V belt pulley.) is mounted in a slot so the tension can be adjusted. It MAY be possible to make the slot longer to allow you to use a longer or shorter toothed belt. As the belt for the DB10 is 124 teeth and yours is 118 teeth then you would need to move the idler by the spacing of 3 teeth which is about 15mm.

Les.

Thread: Keyway Cutting
10/09/2022 12:09:20

This is a method that I used for keyway cutting which avoids using the rack to provide the cutting forces.

img_1549 (medium).jpg

Two lengths of wood are clamped to the bed using long bolts or studding.
This also speeds up the process .

Les.

Thread: mini lathe speed control
03/08/2022 18:14:19

When I first read your post I though forward and reverse were the wrong way round as well as the speed pot working the wrong way. Ignore my comment about reversing the wires to the motor.

Les.

Edited By Les Jones 1 on 03/08/2022 18:14:45

03/08/2022 17:25:27

On the assumption the motor is a permanent magnet type I think you have reversed the two wires to the motor.
I think you have also reversed the connections to the two outer pins on the speed control potentiometer.

Les.

Thread: Resistor Colour Code?
28/07/2022 19:46:31

This will be a fusible resistor that forms the function of a fuse.There will be other failed components that have caused this resistor to fail. You will need to identify and replace ALL the components that have failed.
I think the resistor was probably 2 ohms. 20 x first gold multiplier of 0.1. second gold tolerance. I think the end black possibly indicates that it is a fusible resistor.

Les.

Thread: Switch wire up
05/07/2022 20:15:45

Here is some information on a Santon switch that someone was using with a Myford. It may not be the same as the Santon switch that you have but you can meter out your switch to see if the contact layout is the same as the one in my notes.

contact_layout.jpg

This is from a thread that was probably around 10/03/16 (When I uploaded the picture to the forum.) or 29/09/14. (The date of the file on my computer.)

These are the notes that I uploaded to the thread,

Information on Santon switch which is sometimes fitted to Myford lathes

This is how I understand the switch works.

Forward B to 2, C to 1, A to 3

Reverse B to 2, C to 3, A to 1

 


I have been looking at the way the switch works. There must be 5 contact sets. Each contact set is on a layer of the switch. I will call the front layer layer

1. Terminals C, 3, and A are actually connected to 2 layers each. (You can see the metal connections from 2 adjacent layers bent together.) Terminal C

goes to layers 1 & 2. Terminal 3 goes to layers 2 & 3. Terminal A goes to layers 3 & 4. The contact that I expected to be closed in the for forward position

of the switch (Terminals 3 and A)


Layer 1 Terminals C (and 1 via a wire link) (Closed in forward.)
Layer 2 Terminals C & 3 (Closed in reverse.)
Layer 3 Terminals A & 3 (Closed in forward.)
Layer 4 Terminals A & 1 (Closed in reverse.)
Layer 5 Terminals 2 & B (Closed in forward & reverse.)

 


Wires from motor to switch

Start R

Start S

Run U1

Run U2

 

 


Santon reversing switch connections.


1 To motor start terminal (R ?)

2 Live in

3 To motor start terminal (S ?)

A Live in

B To motor run terminal (R ?)

C | Neutral in
| To motor run terminal (U1 ?)

Where the above connection shows start terminal it means the start winding in series with the centrifugal switch and start capacitor.

Les.

Edited By Les Jones 1 on 05/07/2022 20:16:39

Thread: Telephone Ringback Code?
27/06/2022 14:49:32

Here are some notes I made for the changeover to FTTP

Here is the information on the two ring signals.

For phone service from exchange via copper wires.

Ring sequence.
Voltages with respect to A line. (Plug pin 5)

Static state of B line -50 volts (Plug pin 2)

Incoming call line goes to about +50 volts with ring tone superimposed on it

Ring frequency about 25 hz (About 53 volts rms.)

T = 0 DC level goes from - 50 to +50 volts
T = 1.60 seconds Start of first ring tone burst.
T = 2.0 seconds end of first ring tone burst
T = 2.2 seconds start of second ring tone burst.
T = 2.66 seconds end of second ring tone burst.
T = 4.7 seconds Start of next pair of bursts.

Gap between pairs of bursts about 2.1 seconds.


For phone port on BT Smart Hub 2.

Ring frequency about 25 hz (About 54 volts rms.)

T = 0 DC level goes from +48 to -48 volts
T = 1.50 seconds Start of first ring tone burst.
T = 1.9 seconds end of first ring tone burst
T = 2.1 seconds start of second ring tone burst.
T = 2.5 seconds end of second ring tone burst.
T = 4.5 seconds Start of next pair of bursts.

Gap between pairs of bursts about 2.0 seconds.

Les.


I now have the phone port on the Smart Hub 2 working with two phones and a DECT phone base.

27/06/2022 14:37:49

I was also thinking the problem may be due to the lack of the capacitor that is fitted in the master socket between connections 2 & 3. .Older phones rely on the ring signal being being coupled to terminal 3. Modern phones only seem to need connections 2 and 5 to work. Provided your existing wiring includes a link between connection 3 of all the sockets only one master socket is required. So either add a 1.8 uF capacitor between connections 2 and 3 of one of the sockets OR replace any one of the sockets with a master socket. Regarding REN numbers. I think many modern phones put much less a load on the ringing circuit than a REN number of 1.
I have recently change to BT FTTP and the phone port on the Smart hub 2 works with two of our existing phones and a DECT base. (Non of our phones required the bell wire connection to pin 3 of the socket.)

Les.

Edited By Les Jones 1 on 27/06/2022 14:38:20

Edited By Les Jones 1 on 27/06/2022 14:38:56

Thread: Imperial v Metric Measures
09/04/2022 09:11:16

USB power banks always seem to be rated in mAH. So a 10000 mAH one is really 10 AH.Will the marketing people start to rate them in uAH to make them look bigger. So a 10 AH one would then be called 10000000 uAH.
I remember when metrification first came in I went to by some 6 foot lengths of 2" x 1" I said I want some 6 foot lengths of 2 x 1 but I assume now that will 2 metre lengths of 50 x 25 mm. I was told that they still sold it by the foot.

Les.

Thread: Mill lead screw thread size
08/04/2022 18:12:02

You can work out the pitch from the graduations on the hand wheel scale. The pitch is the distance travelled for one revolution of the hand wheel.If there are no graduations measure how far the table moves for 10 revolutions of the hand wheel and divide that distance by 10.

Les.

Thread: edm machines
01/03/2022 17:13:45

I have only built an EDM based on Ben Flemming's capacitor discharge design. I have modified the servo design to allow it to work with either electrode polarity. I have done this by adding a precision rectifier circuit to the input so that it works with either polarity sense input.

This is the schematic.

feed_servo02.jpg

This is the power supply part so you can see the attenuation and filtering of the sense signal from the electrode.

image1spark_power.jpg

Les.

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