Member postings for Les Jones 1

Hi Peter,
I don't think the live mains input will connecto either 5T3 or 6T3. I think those two connection are a set of contacts that are not use when the contactor is used on single phase. (They would be used on three phase.) I cant find any schematics on line. I would NOT expect the reverse switch, the chuck guard micro and the emergency stop switch to all be connected directly to 3T2. I would expect one of them to be connected directly to 3T2 and all three othe contacts on these items to be connected in series and also in series with the stop button. The wires you mark on / off switch I would expect to be connected to the start button. I SUSPECT that the live input went to 3T2 but do not suggest trying it until you trace the wiring to the reverse switch, the chuck guard micro, the emergency stop, the stop button and the strat button,  Check if the screw in 3T2 is so loose that there would have been room for an extra wire.

Les.

Edited By Les Jones 1 on 07/01/2019 18:14:34

1200 watts is about the same as 1.5 HP so you are not gaining any extra power. Changing the drive ratio as suggested by Bazyle will give you more torque. An alternative way would be to use a two step reduction as on the Chester DB-10G lathe. This is a picture of my lathe before I fitted a three phase motor.

I had to make a new toothed belt pulley and three step pulley as the shaft on the three phase motor was a slightly larger diameter. Remember if you reduce the speed of a motor (DC or three phase.) you have also reduced the power. So if you run your 1200 watt motor a a quarter of it's rated speed it will only be capable of producing 300 watts of mechanical power. (About 0.4 HP.)

Les.

I have found this link that seems to show the same board, There should be two wires from the reversing switch that connect to the motor via the reversing switch. Verify you have the correct ones with resistance measurments. These will connect to A+ and A- on the board. I You connect them the wrong way round the motor directions will be reversed. If this is the case just swap them over. The live from the mains fuse (Yellow ?) will connect to L1 The neutral from the on/off switch will connect to L2. The slider on the potentiometer connects to P2 The wire from the clockwise end of the potentiometer connect to P1 The wire from the anticlockwise end of the potentiometer connects to P3 I suspect that you will have one wire over. I suspect that this will go to the the connector near trimmer R3. I don't know what that connection is. ( On your picture it looks like a green wire goes to it.) You will have to trace where the extar wire goes to to work out what it does.

Les.

Hi John,
I have had another thought. If there are any interlock switches on a chuck guard or cover over the belts or anything else they would be wired in series with the NVR coil. If there are interlocks it would be worth making sure that they show continuity when closed. Is it possible to get the switch out of the box so we can see the underneath of it ? I expect there to be two wires going to the black part at the front of the switch. If there are can you measure the resistance between the ends to see if the NVR coil is open circuit ?

Les.

You need to go to albums, (On the top of the page on the same line that you use to log in.) Then create an album and then upload the oictures to you album. From the box where you type a reply you can then insert the pictures by clicking on the camera button at the top of the reply box.

Les.

If you post some pictures of the old board and the new board there will be more chance of someone being able to help,
Here is a link to the manual, The wiring diagram is near the end of the manual

Les.

Hi John,
I found their 2017 catalogue online but did not fond anything about the power failure release. Is there a coil assembley on your switch ? If so there is probably a contact that keeps that held energised in the foreward or reverse position. If that contact is intermittent it would cause it to drop out and cause the switch to return to the off position, It could also be the mechanism that holds the switch in the forward or reverse position that is faulty. It may only be dirty or needs a drop of oil. If you can post some pictures it may help.

Les.

Hi John,
Can you confirm that the switch actually jumps back to the off position ? I was assuming it stayed in the forward or reverse position but the motor stopped. I think the type number refers to a range of switches and the "X" will be replaced with some code that gives the number of poles and positions.

Les.

Hi John,
I am not familiar with the Kraus and Naimer CA 10x switch but by looking on the web it looks like just a reversing switch with no overload protection. Does it lookf:0"> like this ?

When the lathe stops do you have to wait for some time before it will restart or will it restart straight away ? Is this switch the only control or is there a push button stop and start switch ? About how long does it run for before stopping ?

Les.

Edited By Les Jones 1 on 22/12/2018 10:50:42

Edited By Les Jones 1 on 22/12/2018 10:54:02

Edited By Les Jones 1 on 22/12/2018 10:58:09

Edited By Les Jones 1 on 22/12/2018 11:02:31

I would use a different approach. I would strip off the inner plastic coating to expose the aluminium and make an expanding bush. It would be a short piece of tube with some saw cuts partly along it's length that was pulled onto a tapered bush with a nut and bolt. (Or the bush could be tapped.) Another way that you could try is to make a bush with a hole through is and tap it but only with a taper tap and not all the way through. Put some saw cuts allong it's length from the end that was not fully threaded. When a bolt was screwed in it should expand it when it met the tapered part of the thread.

Les.

Hi Andrew,
I have played them along for a bit by saying I used a Raspberry Pi for internet access. I then Kept them hanging on for a bit saying it was booting up.

Les.

There seems to be a new variation on ones claiming to be from an ISP saying your internet access will be terminated in 24 hours. I have had a few recently claiming to be from something like "The UK cyber crime agency" saying your internet access will be terminated in 24 hours. The difference was the recorded voice was with an English accent.

Les.

How sure are you that the tachometer reading is correct ? I would expect an induction motor running that much below design speed would get very hot..

Les.

Hi Colin,
I did not realise that the screws were so small. I dont think I would risk them for lifting the motor. You might be able to use two pieces of wood to lever it up on the bottom end of the cooling fins. It would be a good idea to get someone to help by steadying the motor as you are levering it up. Another possibility would be to clamp two pieces of wood (Say about 4" x 1" cross section with one or two lengths of threaded rod each side of the motor. Yoh could then screw blocks of wood to the pieces clamping the motor and use jacking bolts to lift against the blocks..

This is the picture from the document in John's link showing the gearbox. It does not show the coupling to the motor very well. I think the end of the motor shaft fits into the end of the shaft item 31 on the drawing.

Les.

Edited By Les Jones 1 on 11/12/2018 22:38:28

Edited By Les Jones 1 on 11/12/2018 22:40:01

Hi Colin,
I would make a plate that fixes on the top end of the motor and fix it to the motor using the three threaded holes that retained the top end plate. Make sure that you get a good length of thread in the threaded holes. I think some reasonable thickness plywood would be strong enough for the plate. Also drill a number of holes (3 or 4) on a PCD a bit larger than the mounting flange. Make some spacer blocks from wood that have about 20mm clearance under the plate. Insert a bolt with a nut on from underneath the plate an put one of the blocks under it. Do the same with all the holes. Use the bolts and nuts to jack the plate up to lift the motor. From the link John has posted it looks like the motor shaft fits into another shaft with a keyway.

Les.

Edited By Les Jones 1 on 11/12/2018 16:51:28

Edited By Les Jones 1 on 11/12/2018 16:54:47

Hi Colin,
The manual I got with my Chester DB-10G lathe contained some drwings of the construction of the lathe. You may be able to get Chester to email you a manual for your mill in .pdf format.

Les.

You will probably have to remove the motor from the mill to get to the screws that bolt the bottom end plate to the casing.

Les.

Hi Colin,
You have now confirmed thet the fault is in the motor. While you have the lamps connected up connect the start capacitor in series with one of them. (As I suggested in my post on 25 Nov at 20:01.) The lamp it is connected in series with should light at almost full brightness as a 150 uF capacitor has a reactance of about 20 ohms at 50 hz. If the lamp lights at near full brightness than the capacitor is probably OK. This is the only way I can suggest testing it without test equipment. From yesterdays tests I am allmost certain that the centrifugal switch is faulty.

Les.

Yes, One bulb to U1 and U2. The other bulb to V1 and W2.

Les.

I should read posts properly. It looks like the centrifugal switch is faulty. U1 and U2 are the run winding and I asked for them to be disconnected to avoid that winding being connected to the start winding connections via the reversing switch and causing false readings. If it was me I would confirm that if two 100 watt. (40 to 150 watt would do.) were connected one to the wires U1 and U2 and the other to V1 and W2 (With those wires disconnected from the motor.) that they lit up when the start button was pressed as if starting the motor in both directions of the forward reverse switch. That would prove that power would be getting to both windings of the motor. I would do that before trying to dismantle the motor to get at the centrifugal switch. When I misread your locations as near Burtonwood I thought I would probably be close enough to you to look at the problem myself as a last resort.

Les.