# Grizzly G4003G electrical ladder logic



## barcuna (Apr 24, 2021)

Does anyone know of a source for a ladder logic diagram for this lathe?  The wiring diagram in the manual is very hard to follow for troubleshooting. Grizzly says that is the only drawing they have.  I could draw it up myself but it would take quite a lot of time and I'm lazy, looking for a short cut.  Thanks


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## Ulma Doctor (Apr 24, 2021)

https://cdn0.grizzly.com/manuals/g4003g_m.pdf
		


the very well written electrical diagrams start on pg83


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## barcuna (Apr 26, 2021)

Ulma Doctor said:


> https://cdn0.grizzly.com/manuals/g4003g_m.pdf
> 
> 
> 
> the very well written electrical diagrams start on pg83


Thanks.  I have that drawing from the manual, but what I'm looking for is a little different.  A ladder logic drawing is more like a computer or PLC program.  It's just a line drawing with components represented by symbols.  It's much easier to use for troubleshooting.
My description might be confusing.  I have an electrical engineering background and a ladder logic diagram is what's normally used for industrial equipment.  I've attached a picture of a example.


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## Ulma Doctor (Apr 26, 2021)

What problems are you experiencing?
I not an engineer, but i diagnose and repair complex systems , often without the luxury of a diagram. Maybe I can be of assistance.


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## barcuna (Apr 27, 2021)

Not having any problems.  The lathe is almost new.  Just preparing for the future, lol!


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## Winegrower (Apr 27, 2021)

It is usually depressing to see the kind of documentation that comes with most industrial or consumer equipment.   Neither lines between boxes nor pictures of wiring nests help any understanding.   I agree with barcuna, there are good conventions for schematics so that components like relays and switches can be readily understood.

i blame this on mechanical engineers.


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## Mitch Alsup (Apr 27, 2021)

BTW does anyone know the difference between a contactor and a relay ??


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## macardoso (Apr 27, 2021)

Mitch Alsup said:


> BTW does anyone know the difference between a contactor and a relay ??


Contactors are typically for controlling loads while relays are typically used for logic control and control signal switching. At least in an industrial environment. They are both magnetically actuated multi pole switches. Contactors usually have more poles than relays.

In circuit boards, relays are typically used for driving loads.


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## Larry$ (Apr 27, 2021)

Mitch Alsup said:


> BTW does anyone know the difference between a contactor and a relay ??


A contactor connects the power to the load. The term sometimes is only applied to the contact block that is a switch but usually means the entire assembly. Which includes the overload block which is wired back into the contactor pickup coil. There can be auxiliary NCNO switches that operate mechanically with the engagement of the contacts. When the remote on button (NO) is pushed power flows to the pickup coil pulling the main contacts together and starting the load. The auxiliary switch mechanically connected to the contacts is closed making a connection to the pickup coil. When the remote NO momentary start button is released the pickup coil continues to get power from the Aux contact block. The off button (NC) is connected between the Aux contact and the pickup coil. When pushed it interrupts power to the pickup coil and that opens the main contacts. Load is then OFF. Those contacts are spring loaded to hold them open if nothing is used to push them closed. Typically they can be manually operated for testing.   
A relay is just a way of making a connection (switch) powered by some other signal. They typically allow a small signal to switch a larger load. Can be solid state or magnetic coil. Magnetic coil relays can have contacts providing multiple NO & NC functions. There are also relays the include other functions like timing. 
Things can look complicated but are usually just lots of simple function parts connected together. 

The wiring diagrams for my industrial edgebander cover many pages, all in Italian!


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## Bi11Hudson (Apr 28, 2021)

Larry$ said:


> Which includes the overload block which is wired back into the contactor pickup coil. There can be auxiliary NCNO switches that operate mechanically with the engagement of the contacts.
> Things can look complicated but are usually just lots of simple function parts connected together.
> 
> The wiring diagrams for my industrial edgebander cover many pages, all in Italian!


Sir, I would beg to disagree with you. A contactor does *not* include an overload deck. When you add the overload deck, a contactor *becomes* a starter. A circuit breaker is not the same as an overload. A circuit breaker protects against high current, an overload protects motors and the like that have high inrush current at startup.

Your description of relays vs contactors is otherwise pretty close on point. I personally take the position than a contactor is just a very large relay, being used for power handling where a relay is to switch control circuits. That description is not a hard and fast rule. I have worked on circuits where the relays were (physically) much larger than a "normal" contactor. It is really dependant on the type of circuits being dealt with.

To the OP, I agree that wiring diagrams are one step above useless. I'll take a ladder diagram any time. I have done many ladder prints for industrial (DC) cranes, as well as machine controls. I *might* could make a ladder diagram had I the wiring diagram for your machine. But it would be a slow process at best as I have had one too many strokes and been retired for many years. But I do agree with other posters that a ladder diagram is much more suitable for troubleshooting. The wiring diagram is for the assembly floor, not practical use.

For what it's worth, I have worked with German (Dutch?) language logic prints, both relay and symbolic. The language is irrelevant, the symbology is what matters. Relay logic is a world of its' own. I lay claim to speaking three languages: English, Electrical, and Computers, not WinDoze, but how a computer works.

.


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## barcuna (Apr 28, 2021)

Yep, I'm pecking away converting the wiring diagram to a ladder logic diagram.  It's a slow process, even for a fairly simple machine (electrically!).  But a little bit more every day and before you know it's done!


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## Larry$ (Apr 28, 2021)

Bi11Hudson said:


> When you add the overload deck, a contactor *becomes* a starter.


*So true!* And when you add a second starter and a timer and wire them to the motor leads correctly, one for Wye and one for Delta you get an "easy on the power company" starter. (Also easier on the electric bill if you have a peak demand meter.) Lots of places in the world require them. One of my European machines has the main motor start that way.


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