Blown band saw circuit.

[Marischal EllisParticipant @marischalellis28661]

Morning

Yes, the Multi meter is max 10 amps.

Pic of micro switch shown. I have tried to chalk it to make it easier to read. The original fell one apart but inside was a couple of metal strips effectively being pressed over or onto. I cannot recall much else. My apologies.

The front of existing switching is the PIc. showing the micro switch as mounted. The red button (bottom right) should have a plastic dust cover on top of it. The running light (top left) I read somewhere is useful in a noisy workshop, so I don't need that now.

The last Pic. shows the emergency stop button wiring diag. They have similarity to each other? I do hope this is not as misleading as much as before.

I tested the resistance of the micro switch. With button NOT pressed-in I got a reading of 1 ((overrange indication). I have assumed this means no connection in this position. With the button pressed DOWN I got varying readings immediately (almost too quick to read) of 7.5, 9.6, 8.4, 6.7, 3.1. The readings whilst still continuing to press down reduced to 0.01 or on one occasion 3.2. It did a count-down through all readings so it took a while on each reading.

I think I have covered all the questions this time so thank you once again for your help but will go over things as requested. Feeling encouraged!

[Les Jones 1Participant @lesjones1]

I have a suspicion that the cover on the left hand side of the machine covers the lower part of the original switch assembly. Am I correct ? Can you post a picture of the INSIDE of this cover showing area around the hole is for the original switch covering about 4 inches around this hole. I think there will be something on the inside of the cover that presses on the micro switch when the cover is closed. This is why I want to see the picture.

Les.

[Marischal EllisParticipant @marischalellis28661]

Afternoon

Here is a Pic.

There is nothing around the switch inside. I have placed switch and plastic 'clip' and loose screw back in loosely to show arrangement with button popping through the cover. All necessary action is from the outside. The loose screw would normally hold the switch in this position. I do hope this helps. Thank you so much.

M

[Les Jones 1Participant @lesjones1]

It is the inside of the panel on the left hand side of the machine that I want the picture of. I think this is hinged at the back of the machine and opens to access the blade and drive rollers.

Les.

[Marischal EllisParticipant @marischalellis28661]

Good Morning

I have taken a pic. of the box showing both halves (all loosely re-assembled). The wires were cut to allow a temporary connection to the mains. The three holes through the back in the top Pic. are for the grommets for feeds in and out.

If you like I can ease apart the micro switch, which I hopefully will not have a use for in the future. Let me know please and I can do it quickly and take a pic. Thank you for all your support once again.

M

[Les Jones 1Participant @lesjones1]

This is still not the picture I asked for. From the second picture picture in your post at 12:46 on 11/10/20 it looks like the black plastic control box is mounted on the die cast right hand side of the machine and it looks like there is a hole in the hinged left hand cover of the machine that allows access to the red and green buttons, the hole for the key and the indicator light. It looks like the hole in the left hand cover does not go down as far as the plunger on the micro switch. I want to see the INSIDE OF THE LEFT HAND COVER so I can see if there is something on the INSIDE of the cover that presses against the plunger of the micro switch when the LEFT HAND COVER IS CLOSED. This would then explain the purpose of the micro switch.

Les.

[Marischal EllisParticipant @marischalellis28661]

I am most sorry. one again. Very poor. Will go into garage and do Pics shortly but I am tied up for the moment. Application and concentration.

M

[Marischal EllisParticipant @marischalellis28661]

I have taken two pics. One of the cover inside and the other of the cover closed. I do hope they are correct.

The open cover was a bit dark so I put some masking tape over the micro switch button as a check. The 'pin' on the cover inside (pointed pencil arrow) aligns perfectly with the button when the cover is closed and the tape was depressed. The loose button was pressed in so, they align with each other.

The other pic shows the cover closed concealing the button from view. Both pics require rotating I am afraid but they are easily understood. M

[Les Jones 1Participant @lesjones1]

We have now confirmed what I suspected in my post on 01/09/20. It has taken 41 days to confirm what would have taken a few seconds if I had been standing next to the band saw.
This is how I suggest connecting thing together.

It will behave slightly differently to the way it was connected in your original diagram, In your original diagram the micro switch was switching the full motor current which was more than it was rated for. It is now only switching the current taken by the coil in the NVR switch. This means that when the cover is open the motor will run while the green button is held pressed. The way it was connected the motor could not be made to run with the cover open.
It is now wired in a similar manner to the schematic in the manual. If you don't want to fit the lamp just don't connect it. (It will work without it.) Whatever physical changes you make to fit the new NVR switch the micro switch MUST be held closed by the left hand cover while it is closed.

Les.

[Marischal EllisParticipant @marischalellis28661]

Gee Whiz Les

I needed so much help it is totally untrue. I was so far off the mark. I will write after I rewire and fit everything together and do the necessary physical changes and checks as long as I can do it in a straight forward way and don't need to ask for further help! I am sure I wont. A big thank you to everyone who has helped, but a special mention to and for Les. I will write more on that later. By chance, I bought some terminals today so will start work tomorrow morning. The physical new arrangement will need to be carefully thought out first.

Best wishes to everyone. Hopefully, it will not take me long. I will sleep well tonight.

M

[Marischal EllisParticipant @marischalellis28661]

Hi

I have enjoyed myself doing a few hours each day cutting, fitting, and assembling the new switch, NVR and so on. over the past few days. I will tomorrow, with a fresh mind check everything over and put the assembled box back into place inside the machine. I have done exactly as said.

My only question arising from this is; should I put an earth connection onto the steel frame? I would use a small bolt /nut probably and wire from the earth wires inside the box. There is no earthing to the steel frame at present.

yours M

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