Thread: Another Waldown Brought Back to Life (I Hope)

I went ahead and checked the motor today. The results are

Cont. Megger
Winding 1. 18 Ohm 88 MOhm
Winding 2. 18 Ohm 108 MOhm
Winding 3. 18.6 Ohm 60 MOhm

The star point wires have been brought out, all the loose bits tied up. I love those EBay Hemastats. I don't know how I managed without them. I have stuck stuff down with Araldite, including all the knots.

I will need to mount the motor on the mill to drill out some broken bolts. One end only has one bolt left intact.

I am now eyeing off the motor off the cylindrical/piston grinder. It is sitting on the bench behind the rickity card table.

Dean

I went ahead and checked the motor today. The results are

Cont. Megger
Winding 1. 18 Ohm 88 MOhm
Winding 2. 18 Ohm 108 MOhm
Winding 3. 18.6 Ohm 60 MOhm

The star point wires have been brought out, all the loose bits tied up. I love those EBay Hemastats. I don't know how I managed without them. I have stuck stuff down with Araldite, including all the knots.

I will need to mount the motor on the mill to drill out some broken bolts. One end only has one bolt left intact.

I am now eyeing off the motor off the cylindrical/piston grinder. It is sitting on the bench behind the rickity card table.

Dean

Originally Posted by Oldneweng

I love those EBay Hemastats. I don't know how I managed without them.

Dean

doctor Dean

Originally Posted by shedhappens

doctor Dean

Don't mix me up with the two Bobs! AB was the surgeon, while BL handed over forceps, swabs etc was how I understood it. They inspired me to explore previously uncharted territory.

Dean

Originally Posted by Oldneweng

I went ahead and checked the motor today. The results are

Cont. Megger
Winding 1. 18 Ohm 88 MOhm
Winding 2. 18 Ohm 108 MOhm
Winding 3. 18.6 Ohm 60 MOhm

Dean...the meggar is used to test to earth

Place a lead on any motor terminal and the other to the motor casing...set the voltage to 500v and press the button, hopefully it will read infinity

if windings have been discnnected from terminal plate then place the lead on each winding ...make sure the windings and lead are isolated from the motor case when testing...you dont want a false connection to earth/motor case

Originally Posted by eskimo

Dean...the meggar is used to test to earth

Place a lead on any motor terminal and the other to the motor casing...set the voltage to 500v and press the button, hopefully it will read infinity

if windings have been discnnected from terminal plate then place the lead on each winding ...make sure the windings and lead are isolated from the motor case when testing...you dont want a false connection to earth/motor case

The Ohm readings are continuity values from a MM. The MOhm readings are from the megger. One wire to each end of a winding and the E wire to the motor case. I should have provided more detail. I hope this is correct. This is what I asked in a previous post and as no-one said no, it figured it must be yes. If not then I guess I am wrong and I need to do some more work on my Chinglish translation skills.

Dean

Originally Posted by Oldneweng

The Ohm readings are continuity values from a MM. The MOhm readings are from the megger. One wire to each end of a winding and the E wire to the motor case. I should have provided more detail. I hope this is correct. This is what I asked in a previous post and as no-one said no, it figured it must be yes. If not then I guess I am wrong and I need to do some more work on my Chinglish translation skills.

Dean

ah..it looks like you had done it correctly. ( the way you laid it was not clear hence my reply)

Originally Posted by eskimo

ah..it looks like you had done it correctly. ( the way you laid it was not clear hence my reply)

Yes. But remember this. I wrote it clearer on the envelope at the time. LOL

Thanks for your help.

Dean

Originally Posted by Oldneweng

Yes. But remember this. I wrote it clearer on the envelope at the time. LOL

Thanks for your help.

Dean

you need to put a stamp on it...aus post frowns on those trying to get free postage

I have reassembled the motor and connected it to the VFD. It runs well except for a bit of noise.

The motor has been dropped at some stage. On the drill press or off I cannot say.



Motor Rear Plate Repair.jpgMotor Inside Rear 2.jpg

If you look at the top screw hole you can see a lug inside it which serves 2 purposes. I locates the end plate inside the main case and it holds the baffle plate/ring, visible behind the fan in pic 2, in off the fan. The right side and bottom lugs have been broken off and 3 of the screws holding the end plate on were broken off. I managed to remove 2 of the screws, but had to drill and tap the 3rd one. This extracted the threads, so all is good there. The noise was, I presume from the fan hitting the baffle plate. As shown in pic 1, I milled a small flat and drilled a 3mm hole. I then made a 3mm diam pin which I have stuck in with loctite. I am hoping the end plate position will be ok. Once I get it back together on the weekend I will consider this. The pins are only to press the baffle plate in against machined surfaces behind it to hold it in position.

Dean

I put the motor back together and tried it today. I have got rid of the rattle, but there is still a noise. I suspect that it is caused by either

Bearings
Misalignment due to missing locating lugs
Misalignment due to a twisted case, from the drop.

I did have a play with the VFD for a short while. The motor is rated at 1430rpm (Wye connection). At 50Hz it was clocked at 1400rpm. At 140Hz it was clocked at about 4200rpm.

Dean