ok. you were asked questions in post #23, 32, and 36 which you've yet to answer. does that mean that you're satisfied with cork_ie's drawing as is, and we're done here? or does it mean that you're going to go rewire the machine per cork_ie's drawing and get back to us? or some other thing?

Sorry, the thread just seems to be in limbo and I'm not sure if you feel your issue has been resolved or if you're still waiting for something more.

I'm feeling mischievous http://www.youtube.com/watch?v=1nBwfZZvjKohttp://forum.allaboutcircuits.com/ww.youtube.com/watch?v=1nBwfZZvjKo
Hee Hee

 

I'm feeling mischievous http://www.youtube.com/watch?v=1nBwfZZvjKohttp://forum.allaboutcircuits.com/ww.youtube.com/watch?v=1nBwfZZvjKo
Hee Hee

How fitting! I'm piddling around on AAC while I'm supposed to be studying chemistry and doing my homework. On that note, I'm out. I'll be back this evening.

 

Another one is Parkinsons Law
"Work expands so as to fill the time available for its completion".

I often feel that way at work. But then I work for the government so its expected.

To answer Strantor's question I think I would like to go with the LOGO! PLC if possible. I think this is a dead end. Wiring it up back to factory locks it into one function. Press button/Something happens. And the same thing happens everytime

Correct me if I'm wrong because I haven't researched it too much, BUT, with the LOGO PLC controller I can program different functions.
I can program the saw to raise on its own when it hits the bottom limit switch. Or I can program it to shut off solenoid and do nothing.
I think a PLC would expand the capabilities of the saw and add to its value.
I like the idea of retrofitting and the reuse of stuff. We live in a disposable society.

 

I often feel that way at work. But then I work for the government so its expected.

To answer Strantor's question I think I would like to go with the LOGO! PLC if possible. I think this is a dead end. Wiring it up back to factory locks it into one function. Press button/Something happens. And the same thing happens everytime

Correct me if I'm wrong because I haven't researched it too much, BUT, with the LOGO PLC controller I can program different functions.
I can program the saw to raise on its own when it hits the bottom limit switch. Or I can program it to shut off solenoid and do nothing.
I think a PLC would expand the capabilities of the saw and add to its value.
I like the idea of retrofitting and the reuse of stuff. We live in a disposable society.

To be brutally honest, I think the PLC a dumb idea, unless you're doing it just for the educational value. You're almost there right now. Just a few easy wiring changes and your saw will do what it's supposed to. It didn't need anything more sophisticated than 4 relays when it was made, and still doesn't.
Now, if you were looking to expand the functionality of it, maybe tie in a conveyor that stops and waits for the saw to cut, and then an ejector, then then converting to PLC control would be a worthwhile endeavor, but as it stands, you'd be reaching around the world to scratch your ass.

 

I don't know how it was wired up coming from the factory.

How is the variable speed you refer to controlled at the moment, or at least the last time this thing was working?

I need to know exactly what you want to do, so that I can alter the schematic to suit.
Can you please post a step by step sequence of operations.
i.e.
1)Turn on main switch
2) Start Saw
3) Start Hydraulic Pump
4) etc. etc.

This thing looks like it fell overboard off Noah's Ark and I doubt it currently has any fancy electronics on it.

Turn on power at main switch

Operation assuming that the saw arm is in the resting position, at the lowest possible travel.

Functions that are possible:
- Turn on Saw Motor
- Turn on Hydraulic Motor
- Raise Saw Arm
(It should not be possible to lower the arm. Lower limit switch should be tripped so no power to the 'Lower Button')


Raising the saw arm:
Raise saw arm by pressing Raise Solenoid Button.
Contactor does not latch. Operator has to hold the button to keep contactor engaged.
IF upper limit switch is tripped then the Raise Solenoid contactor disengages.

Operations assuming saw arm is above its lower travel limit.


Lowering the saw arm
Operator presses button and Lower Solenoid contactor latches.
Tripping lower limit switch disengages the lower solenoid contactor.
Pressing the Raise button should disengage the lower solenoid contactor and engage the Raise contactor

It should be possible to start the saw motor and hydraulic motor at any time.

The description above would work for me. If I could get it to do that much I would be happy.

 

ok. you were asked questions in post #23, 32, and 36 which you've yet to answer. does that mean that you're satisfied with cork_ie's drawing as is, and we're done here? or does it mean that you're going to go rewire the machine per cork_ie's drawing and get back to us? or some other thing?

Sorry, the thread just seems to be in limbo and I'm not sure if you feel your issue has been resolved or if you're still waiting for something more.

#23 - The buttons have both NO and NC contacts. They are shown in the drawings I uploaded. They are labled on the buttons. Could be hard to see in the drawing.

#32 - I have a knurled knob on my saw that controls the variable hydraulic feed. Just like the one in the video.

#36 - The unknown button is still unknown to me. I think its a power enable button or emergency stop. The knob will twist in as its pushed and it locks at the end of the travel. I have a CNC machine that has an emergency button that operates that way so I'm assuming its an emergency stop. Also considering its a dangerous piece of industrial equipment I think its an emergency stop button. Its has 24V leads to the saw motor and hydraulic motor buttons.

I'll wait and see what Cork_Ie comes up with for a drawing.

 

Turn on power at main switch

Operation assuming that the saw arm is in the resting position, at the lowest possible travel.

Functions that are possible:
- Turn on Saw Motor
- Turn on Hydraulic Motor
- Raise Saw Arm
(It should not be possible to lower the arm. Lower limit switch should be tripped so no power to the 'Lower Button')


Raising the saw arm:
Raise saw arm by pressing Raise Solenoid Button.
Contactor does not latch. Operator has to hold the button to keep contactor engaged.
IF upper limit switch is tripped then the Raise Solenoid contactor disengages.

Operations assuming saw arm is above its lower travel limit.


Lowering the saw arm
Operator presses button and Lower Solenoid contactor latches.
Tripping lower limit switch disengages the lower solenoid contactor.
Pressing the Raise button should disengage the lower solenoid contactor and engage the Raise contactor

It should be possible to start the saw motor and hydraulic motor at any time.

The description above would work for me. If I could get it to do that much I would be happy.

Done, see new grey line. one more wire will have to be ran through the conduit to the control button box. is this possible?

#23 - The buttons have both NO and NC contacts. They are shown in the drawings I uploaded. They are labled on the buttons. Could be hard to see in the drawing.

#32 - I have a knurled knob on my saw that controls the variable hydraulic feed. Just like the one in the video.

#36 - The unknown button is still unknown to me. I think its a power enable button or emergency stop. The knob will twist in as its pushed and it locks at the end of the travel. I have a CNC machine that has an emergency button that operates that way so I'm assuming its an emergency stop. Also considering its a dangerous piece of industrial equipment I think its an emergency stop button. Its has 24V leads to the saw motor and hydraulic motor buttons.

I'll wait and see what Cork_Ie comes up with for a drawing.

I agree. E-stop.

 

The knob will twist in as its pushed and it locks at the end of the travel.

Does it automatically "unlock" or must you do that manually. If it is done manually (untwisting it), it's not a very good "emergency stop". It could be a Master ON supplying power to the machine before the operation of any of the other buttons. That would be a "child proof" power on button ... per se.

 

Strantor's modified drawing seems to fulfill all your requirements.

You just need to verify the emergency stop.

Don't forget to check whether the contactor coils are AC or DC

I look forward to a YouTube video, being up soon, with this thing working.

 

Thanks. I'll let you know how it works out.

 

An update on this issue.
I was able to wire it up and get it to do the basic functions.
Something struck me as a little odd as I was redoing the wiring.
I have 2 limit switches. One for the lowering function and one for the raising funciton.
Both limit switches have a set of NO and NC contacts.
And here is what I think is the strange part (being new to this stuff)
The upper limit switch will close the normally open contactor when it reaches the upper limit of travel. It opens the NC at the same time.

What do you think the reasoning is for closing a NO contactor? A coworker seems to think that it is to enable something else. Maybe it enables the lower push button?

 

It is quite common to use the same type of limit switch in a machine , even if there are unused connections.

This helps to minimise spare part inventories and reduce costs. It is quite likely that they are just unused.

All I can say is that the circuit diagram I drew for you as modified by Strantor will fulfil all the functions requested on your list in post #45

 

Yes it does function as requested.