# Press controls?



## Sparkee (Sep 22, 2009)

Anyone know a good website on press controls?


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## McClary’s Electrical (Feb 21, 2009)

Too vague


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## HARRY304E (Sep 15, 2010)

mcclary's electrical said:


> Too vague


WOW! that was helpful.:blink:


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## HARRY304E (Sep 15, 2010)

Sparkee said:


> Anyone know a good website on press controls?


Try this.

http://www.toledointegratedsystems.com/products/press_controls/index.php


http://www.ciecocontrols.com/second_level.cfm?att=1


http://www.niroinc.com/pharma_systems/tablet_press_control_systems.asp


http://www.dynasys.org/Printing_press.htm


http://www.presscontrols.co.uk/


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## Sparkee (Sep 22, 2009)

Sorry about being vague, I had to rush off to work. A client of mine has tasked us to rebuilt the electrical controls on some mechanical brake presses. As always OSHA is a good place to start but I was looking for a web site similar to this one but where the subject is presses and associated industrial controls. I have installed anti-tie down circuits, light curtains, safety guards along with trouble shooting presses but 
I was just looking to talk to people in the same field.


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## varmit (Apr 19, 2009)

I have worked on many different types of presses- steel, cardboard, paper and printing.

What type machine are you dealing with? Is it cyclic or flywheel? Electric only, or electro hydraulic? Individual parts or continuos cycle? Control- manual/relay or PLC? Stand alone or network?

Be glad to help if I can, but i would need some details to be helpful.


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## Sparkee (Sep 22, 2009)

varmit said:


> I have worked on many different types of presses- steel, cardboard, paper and printing.
> 
> What type machine are you dealing with? Is it cyclic or flywheel? Electric only, or electro hydraulic? Individual parts or continuos cycle? Control- manual/relay or PLC? Stand alone or network?
> 
> Be glad to help if I can, but i would need some details to be helpful.


It's a Precision brand press, flywheel, electro-mechanical, continuous cycle. It appears to have been "worked on" several times so all the prints they gave me don't match. We got it to work in inch and continous but we cannot get it to work in single stroke (it will only travel 180 degrees) and top stop will not work. It has a capacitor, resister, rheostat portion of the circuit that I have never seen before and I'm not sure of it's function but I think it's at the root of our problem. There is also a device that looks like a bridge rectifier but it only has 2 wires going to it. It uses cam switches to tell it where it is but I don't measure any voltage going to it. It's all relay logic and no PLC's or encoders.


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## joethemechanic (Sep 21, 2011)

Sparkee said:


> It's a Precision brand press, flywheel, electro-mechanical, continuous cycle. It appears to have been "worked on" several times so all the prints they gave me don't match. We got it to work in inch and continous but we cannot get it to work in single stroke (it will only travel 180 degrees) and top stop will not work. It has a capacitor, resister, rheostat portion of the circuit that I have never seen before and I'm not sure of it's function but I think it's at the root of our problem. There is also a device that looks like a bridge rectifier but it only has 2 wires going to it. It uses cam switches to tell it where it is but I don't measure any voltage going to it. It's all relay logic and no PLC's or encoders.



I take it this is an electric over pneumatic type clutch?

Pictures?


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## Sparkee (Sep 22, 2009)

joethemechanic said:


> I take it this is an electric over pneumatic type clutch?
> 
> Pictures?


Yes. It's a duel solonoid Ross valve controlling the clutch. I'll get pictures next time I'am there. I'm sure that would help a lot.


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## varmit (Apr 19, 2009)

Sparkee said:


> It's a Precision brand press, flywheel, electro-mechanical, continuous cycle. It appears to have been "worked on" several times so all the prints they gave me don't match. We got it to work in inch and continous but we cannot get it to work in single stroke (it will only travel 180 degrees) and top stop will not work. It has a capacitor, resister, rheostat portion of the circuit that I have never seen before and I'm not sure of it's function but I think it's at the root of our problem. There is also a device that looks like a bridge rectifier but it only has 2 wires going to it. It uses cam switches to tell it where it is but I don't measure any voltage going to it. It's all relay logic and no PLC's or encoders.


These older presses are notorious for the OEMs dreaming up unique (odd ball) ways of doing things. You are way ahead if you have any documentation to start from. Most of the old junk, that I work on, has no documentation at all. Your best friend can be a long time operator of this machine. They may not know the controls, but they would know the sequence of operation and the machine function.

Since, obviously, I can't look at the machine, I will make some guesses and assumptions:

The stopping at 180 degrees is probably a cam switch or position switch or the relay controlled by these switches. These machines usually have a logic string that looks at the discharge of the machine before allowing the second 180 degrees of rotation. This is to help prevent jams.

The cap, resistor and pot are probably the adjustments for the clutch reaction time. The two wire "rectifier" is probably a snubber to make a coil drop out reliably.

I have seem many odd and unusual control voltages on these type machines. 
In addition to the "normal" voltages, I have seem anything from 5 VDC to 60 VAC.

If you can get an accurate sequence of operation, and the owner will spend the money, It CAN be quicker and cheaper to do away with the old wiring and start over. An encoder feedback and a small PLC can be a cost effective way to retrofit a machine.

Good luck,
Harry


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## Sparkee (Sep 22, 2009)

I appreciate your reply. Always so much to learn! This work can be frustrating at times but it is never boring.


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## John (Jan 22, 2007)

I did some punch press controls about 10 years ago. A word of caution on doing any alterations to the existing press controls. If something goes wrong you will be first in line when they start pointing fingers. This is something that I wll NOT do now ....troubleshoot yes , new install no.

Ross air control valves have to have 2 control circuits and a reset circuit in order for it to work the was it was designed to be used.

Best bet wold have somebody else supply the controls and maybe you install them. 

Rockford Controls


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## John (Jan 22, 2007)

varmit said:


> If you can get an accurate sequence of operation, and the owner will spend the money, It CAN be quicker and cheaper to do away with the old wiring and start over. An encoder feedback and a small PLC can be a cost effective way to retrofit a machine.
> 
> Good luck,
> Harry


I have done some in the past and would not recommend creating a new control system due to the highly sue happy society we now live in. 

Ya got to know when to hold em and when to fold em and run for the door.


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## varmit (Apr 19, 2009)

John said:


> I have done some in the past and would not recommend creating a new control system due to the highly sue happy society we now live in.
> 
> Ya got to know when to hold em and when to fold em and run for the door.


Unfortunately, I will have to agree with you. I always try to to be liability conscious and sometimes it is better to walk away. Even if you improve the machine operation, and something goes wrong, that had nothing to do with your work, you can still be "under the bus". Of course, only repairing a machine will not absolve a person of liability either. Any entity can sue another over anything and your only defense will be proper procedures and documentation. There are no 100% safe business undertakings: Reasonable risk hopefully equals profit.


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## John (Jan 22, 2007)

This issue of designing press controls not only falls within the NEC but also OSHA. I real big issue is section 1910.217(e)(2) of the OSHA regulations is; _Modification. It shall be the responsibility of any person modifying a power press to furnish instructions with the modification to establish new or changed guidelines for use and care of the power press so modified._​When doing this type of work you really need to know what you are doing and be current in your understanding of all the regulations pertaining to presses. 

http://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=STANDARDS&p_id=9841

Here is a picture of a press control station for a 90 ton punch press that built the controls for.

And the keys are not supposed to be left in the key switches.:no:

View attachment 10896


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