Bandsaw cut out switch wiring

[Sidewinder]

carbon, electrically 13/14 was below b on the coil.
You should never have control components both side of a contactor coil, that is very bad design and classed as dangerous in machinery control standards.
Just put all the "off" controls in the leg to a & connect b directly to one output of the control Tx, and ground that leg of the control Tx to make teh control system TN-S.
I thought that there were fuses in the control circuit, in the Tx primary & secondary?

 

[scottmk1]

Ok, I've removed the bridging wires from the indication lamps, and replaced the fuse. The fuse doesn't blow, but pushing the start button still doesn't operate the contactor.

 

[WorkshopChris]

PS I'm going cross-eyed so E&OE

Your doing better than me, its hard when its all on different pages .
Would be so simple when the machine is in from to you.
In the past i have found it simpler to rip out all the old control wiring and start form scratch.

 

[scottmk1]

simpler to rip out all the old control wiring and start form scratch.

That very thought keeps running through my head.

 

[rtbcomp]

...
In the past i have found it simpler to rip out all the old control wiring and start form scratch.

Me too. What are the various indicator lights supposed to do?

 

[scottmk1]

One light shows that the main power is on, one shows that the main motor is running, and the other shows that coolant pump is running.

 

[carbon]

carbon, electrically 13/14 was below b on the coil.
You should never have control components both side of a contactor coil, that is very bad design and classed as dangerous in machinery control standards.
Just put all the "off" controls in the leg to a & connect b directly to one output of the control Tx, and ground that leg of the control Tx to make teh control system TN-S.
I thought that there were fuses in the control circuit, in the Tx primary & secondary?

I was replying to the first picture that rtbcomp added but has since replaced with a modified one

 

[Sidewinder]

carbon,
The switches are electrically in the same place is what I am getting at in both the diagrams by rtbcomp.

 

[carbon]

Sorry it does look like they are probably didn't study it enough after he put that "I have the contactor powering up as soon as the mains is switched on"

 

[rtbcomp]

This the complete circuit diagram as close to the 2nd wiring diagram as I can make it, ie correcting the errors in that diagram. I reckon this would work OK subject to the caveat in Sidewinder's post #61.



For the sake of simplicity I would wire the power-on bulb straight across the transformer secondary and omit the NN contacts on the power switch.

 

[rtbcomp]

Reckon this should do it



The order in which the various control switches are wired would depend on the layout of the machine, as long as they're all in series and with the start button in parallel with the latching contacts on the contactor you should be OK

 

[Sidewinder]

Reckon this should do it

View attachment 92919

The order in which the various control switches are wired would depend on the layout of the machine, as long as they're all in series and with the start button in parallel with the latching contacts on the contactor you should be OK

Yep that would be OK, and compliant pretty much.
Just fuse it if possible, one in each of the Tx supply phases, and the wire to the limit switch, then earth the wire between the N contact & the Tx, I'd prefer the N contact the other side of the lamp though.

 

[scottmk1]

Thanks for doing those much better drawings than mine. I will compare & change the wiring to suit the last drawing tomorrow if I get time, and hopefully it's a success!

 

[scottmk1]

Right I've rewired it as per @rtbcomp 's last drawing and it works! I need to tidy it up and then it's all good. Thanks to everyone who helped.

 

[rtbcomp]

^^ Phew! And you're still alive.

Did you add fuses as per Sidewinder's suggestion? Worth doing, at the very least put one in the secondary of the transformer.

 

[scottmk1]

Yep still alive!! I haven't added the fuses yet, but when I come to tidy up the wiring I will get fuse holders & fuses to complete it as per Sidewinders suggestion. I just rewired it to your drawing quickly this evening to prove it works, I'm away with work for a few weeks as of tomorrow so wanted know it would work & now I can order the bits I need whilst away.

 

[rtbcomp]

Give me a shout if you want a DXF of that drawing, you can then add your wire colours &c and keep it with the machine.

 

[ukracer]

Holy thread resurrection. Lol

What would I need to enter ,to search for the trip switch.
Whilst the switch is still there and the arm drops on it after cutting it does not turn off the blade/motor.

 

[Pete.]

Push the switch down with your finger. If it stops the motor you need to adjust it. If it doesn't you need to fix it.

 

[ukracer]

Push the switch down with your finger. If it stops the motor you need to adjust it. If it doesn't you need to fix it.

I am pretty sure it does not cut anything out. I will check later.