Re: Which thickness CY cable do I need for 1.5kW spindle?
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Originally Posted by
paulus.v
Do you have a hair dryer at hand? Check the cable and power. Mine has 1700W and a 2x0.75mm2 cable. And is german made.
Fine. Now, run that hair dryer for 8 hours non-stop and see what happens... :eagerness:
Hair dryers are NOT high frequency controlled equipment, they have a tiny motor and they are not designed to be run for more than a few minutes a time so you can't really take that as a good example. My drilling machines have 1.5mm2 cables, they are also German made, and none of them are over 1kW. Why? Because they are designed for sudden current rushes and for long usage time.
Quote:
Originally Posted by
paulus.v
Now regarding the question in this thread, I would never use a 0.75mm2 "normal" stranded cable in a CNC machine. Since all the cross-sections are composed of thin wires with the same diameter, a larger cable will last longer. If/when half the wires of the 0.75mm2 conductor (only 10-12 of them) will be broken, probably the rest will blow. For a 1.5mm2 cable, three times the number of wires needs to be broken to come to the same situation.
That is yet another good argument for a stronger cable. On the other hand, if you handle the cable as you supposed to handle and don't bend it more than it is specified for *AND* use the cable type which is designed for the application (i.e. flexible cable chain use) than you should not have any broken wires during the life time of your machine. Remember that I am talking about quality cables, not the one used in the hair dryer.
Quote:
Originally Posted by
paulus.v
Using special flexible fine stranded cables, even 3x0.5mm2 will be enough for a 3 phase 1.5kw spindle on a short distance :playful:
Yes, of course. I have never claimed otherwise. Just that I can't really see any *GOOD* reason for not using something stronger than 0.75mm2. Never the less, there is a group of people who prefer the easiest approach, which is using the thinnest possible cables. Beats me why, I don't understand that philosophy and prefer to have margins if I can. On the other hand... so far I have not had any electrical issues, and I don't expect to have any later on.
Re: Which thickness CY cable do I need for 1.5kW spindle?
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Yes, of course. I have never claimed otherwise
I thought you claimed it here:-
Quote:
It is thinner and lighter but it should be 1.5mm2. 0.75mm is OK for control signals but actually too thin for the power
Well you appear to have jumped on the op's post nearly 3 months after he last posted and muddied the waters quite well.
I think you need to take a good look at your own machine before nit picking others.
I will not be posting any more on this subject. So please lets not take any more space on his post.
By all means start one of your own.
Re: Which thickness CY cable do I need for 1.5kW spindle?
Quote:
Originally Posted by
A_Camera
Generally speaking, yes, 0.75mm2 is enough for most cases for the spindle, but why use something as thin as that if 1.5mm2 is safer, stronger, not much heavier, better suited for the purpose and hardly much more expensive. Can you come up with ONE good reason other than most people don't continually use up more than 5A?
I could but won't get into slanging match with someone so narrow minded. I'm also not saying I would have used 0.75mm2 because I wouldn't have. However only because I have 1.0mm2 & 1.5mm2 which use all the time. If I'd only had 0.75mm would have used it.
The point of my first post was more to re-assure the OP "Bee" that his choice, which he'd already purchased before you posted would be fine. This by now he surely knows because some Muppet started up the thread again 3 mth's after he posted.!!
Re: Which thickness CY cable do I need for 1.5kW spindle?
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Originally Posted by
JAZZCNC
I could but won't get into slanging match with someone so narrow minded. I'm also not saying I would have used 0.75mm2 because I wouldn't have. However only because I have 1.0mm2 & 1.5mm2 which use all the time. If I'd only had 0.75mm would have used it.
The point of my first post was more to re-assure the OP "Bee" that his choice, which he'd already purchased before you posted would be fine. This by now he surely knows because some Muppet started up the thread again 3 mth's after he posted.!!
OK, so you would not use 0.75mm2, just want to comfort someone who bought the cable... well, the reason for the Muppet to start up the thread LESS than 2 mnts after Bees last post was to try to open the minds of those who are not sure, so they just follow the stream and go after the majority on these forums. I think that can hardly be called narrow minded, more like an effort to help. Considering the costs of the cable, and compared to the price of the CNC the "use what I have available" principle is really very narrow minded and wrong. Apparently you are more keen on name calling than admitting that I was right, there are ONLY advantages of a stronger, better cable, no disadvantages. You don't answer my question because there is just one answer. Anyway, at least in this post, you made it clear that the 0.75mm2 would have not been your choice, so basically, we actually agree.
...and in all honesty, if you really know what I think you know, then I don't think you would have used 0.75mm2 cable if that was all you had at home. I think you would have done the same I would have done, ordered 1.5mm2 and possibly used the thinner one until the better one arrives... :toot:
Like I said, what works and what is right are not necessarily the same.
Re: Which thickness CY cable do I need for 1.5kW spindle?
Quote:
Originally Posted by
A_Camera
It is thinner and lighter but it should be 1.5mm2. 0.75mm is OK for control signals but actually too thin for the power.
You do not say that you prefer or recommend using thicker cables to be on the safe side or you normally have them at hand or you don't mind wasting a valuable metal with finite resource here on earth. But you say that a 1.5KW spindle cable should be 1.5mm2 and the control cables 0.75mm2 (when most control cables are 0.25mm2). This approach is all wrong!
Re: Which thickness CY cable do I need for 1.5kW spindle?
Quote:
Originally Posted by
Clive S
I thought you claimed it here:-
Well you appear to have jumped on the op's post nearly 3 months after he last posted and muddied the waters quite well.
I think you need to take a good look at your own machine before nit picking others.
I will not be posting any more on this subject. So please lets not take any more space on his post.
By all means start one of your own.
Sorry for disturbing the peace, but the way I see it is that I was not the one throwing the mud. I made a short one line comment and not criticized you or anyone else, all I said was:
Quote:
It is thinner and lighter but it should be 1.5mm2. 0.75mm is OK for control signals but actually too thin for the power.
Actually, going by the book (the manual of my VFD), even that statement is wrong because for the 1.5kW the cable should be 2.5mm2 but that is simply too thick and really over engineered, so 1.5mm2 is more realistic.
The thread would have been dead by now but apparently you, and some other people could not stay away from it, so it lives on. I don't mind that, but it would be more useful if people could keep their heads cool and would not throw mud just because I don't follow the stream and have a different opinion. I was also NOT nit picking on other people's machines, but you have to remember that this forum is visited by many total newbies who experience a lot of electrical issues. One way of helping is to give factual advice, not emotional.
BTW, Why are you saying that I need to take a good look at my own machine? I am looking at my machine, and regarding electrical installations, I am not only using several DVMs but also an oscilloscope, and in fact, occasionally two oscilloscopes at the same time. Apart from that, I am reading the manuals of every item that comes with a manual, not just guessing and go after what other people use or claim on the internet. Never the less, I could have missed something, so if you have found something wrong please let me know. I am in the process of upgrading and welcome all comments. I have no emotional attachments to my machine so I am ready to change almost anything if it is for the better. :eagerness:
You are though right about one thing, there is not much more to say about the subject, though it may pop up again, or someone might start a new thread with the same question...
Re: Which thickness CY cable do I need for 1.5kW spindle?
Quote:
Originally Posted by
paulus.v
You do not say that you prefer or recommend using thicker cables to be on the safe side or you normally have them at hand or you don't mind wasting a valuable metal with finite resource here on earth. But you say that a 1.5KW spindle cable should be 1.5mm2 and the control cables 0.75mm2 (when most control cables are 0.25mm2). This approach is all wrong!
Yes, well... many people have electrical issues...
I think that line is pretty clear, but sure, this is the internet, so if something can be misinterpreted you can be sure someone WILL misinterpret it and start a stupid fight about it.
Regarding the environmental issues... well... the way I see it is that basically EVERYONE on this forum, and every other similar forum, is wasting valuable metal with finite resources here on earth, because hand on your heart... how many of us MUST have the machines we have? To me this is just a hobby, as it is for most people on these forums. You, and everyone else on this forum (including myself) are HUGE contributors to global warming, the using up of finite resources and everything else environment activists can come up with. So, please don't beat your chest and be proud about yourself just yet or accuse me for being an enemy of the earth... you know nothing about me or how I am living, so leave that out.
Besides, who says that the cable must be wasted? It can be used in another project or sold to somebody else for re-use.
Re: Which thickness CY cable do I need for 1.5kW spindle?
Quote:
Originally Posted by
A_Camera
Apparently you are more keen on name calling than admitting that I was right, there are ONLY advantages of a stronger, better cable, no disadvantages. You don't answer my question because there is just one answer. Anyway, at least in this post, you made it clear that the 0.75mm2 would have not been your choice, so basically, we actually agree.
I wasn't name calling more stating the obvious. IMO it's muppet with over active Ego that posts reply to question which had been answered already and acted upon by the OP months ago.!
I don't doubt your knowledge of electricker and in principle Yes your correct so if your Ego needs a massage I'll glady ablige and say I agree that 0.75mm shouldn't be first choice.
However the fact still remains 0.75mm2 would and will work perfectly fine. All your arguments regards Cable strength, ridgidty etc are mute because it's stupid thing to rely on cable for strength when it should be supported with bracket. The Only thing that matters is if cable can handle the load of the device it's powering while in prolonged use and clearly it can.
Quote:
Originally Posted by
A_Camera
...and in all honesty, if you really know what I think you know, then I don't think you would have used 0.75mm2 cable if that was all you had at home. I think you would have done the same I would have done, ordered 1.5mm2 and possibly used the thinner one until the better one arrives... :toot:
Why would you presume to predict what I would do.? . . . I don't know me so you or anyone else stands NO chance predicting my actions.!!
If I'd took the time effort to fit it then I'd consider it safe and it would stay on. The ONLY time I might do this is in emergency situation to get machine up and running.
Quote:
Originally Posted by
A_Camera
Like I said, what works and what is right are not necessarily the same.
This is contradiction.!! . . . . . If it's working Correctly then it's Right.!!
Re: Which thickness CY cable do I need for 1.5kW spindle?
Quote:
Originally Posted by
JAZZCNC
This is contradiction.!! . . . . . If it's working Correctly then it's Right.!!
Glad to hear it JAZZ I was almost ready to swap out the 6560 on the Sieg conversion but now you say its right I will leave it where it is!:victorious:
Re: Which thickness CY cable do I need for 1.5kW spindle?
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Originally Posted by
lucan07
Glad to hear it JAZZ I was almost ready to swap out the 6560 on the Sieg conversion but now you say its right I will leave it where it is!:victorious:
Performance upgrade is different animal.!! . . . Fatter cable won't make spindle go any faster.:stupid:
