Generally I don't use N/O types for limit switches, they dont cover broken connections. Could use two N/C in parallelQuote:
Originally Posted by magicniner
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Generally I don't use N/O types for limit switches, they dont cover broken connections. Could use two N/C in parallelQuote:
Originally Posted by magicniner
Series for NO, so the circuit only closes when both close.Quote:
Originally Posted by cropwell
Parallel for NC, so the circuit only opens when both open.
:D
I'm planning this with my Chester Mill CNC conversion, I've become accustomed to being able to shut down my X7 and know there will be no positional errors when I turn it on the next day, select the WCS and slot a part into a fixture, I can't imagine going back to having to indicate every time I fire a machine up, I don't think a homing system which requires you to re-indicate a fixture which hasn't been moved is acceptable, in fact I think that's the definition of Useless.
Equally well, N/C types don't cover short circuits, had a few of those in my time.... :topsy_turvy:Quote:
Originally Posted by johnsattuk
Why not have 1 NC and 1 NO, then it wouldn't matter whether you wire in series or parallel :joker:Quote:
Originally Posted by magicniner
It took some time for me to understand the second part of the reply as I don't get what part the Wildlife Conservation Society play in CNC. If I am cutting a few parts and have to turn off the machine then I zeroise the Z and 'Ref All Home' to send the X and Y back to the zero point. That way, when I switch on the next day, I know here the machine is.
BTW, I love these things, Engineers Lego......
https://www.arceurotrade.co.uk/Catal...-Metric-Blocks
Cheers,
Rob
:thumsup::thumsup::thumsup:Quote:
Originally Posted by cropwell
My point is that with a well designed and implemented system that shouldn't be, and in fact isn't necessary :DQuote:
Originally Posted by cropwell
Work Coordinate System BTW
Hi Nick,Quote:
Originally Posted by magicniner
WCS - I looked it up on Google. I actually rejected the idea that it could be the wildlife thing, toyed with Workflow Control System, Warehousing Computer Systems and World Coordinate Systems (Getting close there - that was defined as something to do with CNC). I did not think that with this latter CNC TLA you needed to know the precise latitude and longitude to define the machines X,Y 0,0, but apparently there it is. Even more incomprehensible is the UCS (universal Coordinate System, which even takes into account the Space/Time Continuum.
Maybe it is time that we had some TLA control, such as an Acronym Registration System (ARS). Maybe I could become an Acronym Registration System Executive (ARSE), although a lot of people probably think I already am.
Rob-T
An Acronym is a set of letters pronounced as a word, if the individual letters are voiced as in VCR or TLA it is an Initialism thus, somewhat amusingly, TLA is not a TLA :D
To get back on topic....
I do not use work offsets very often, which I presume depends on the accuracy of determining machine zero by homing all axes (axises ?). Most of what I do is one-offs and for that I zeroise locally when the piece is bolted down. If I have to do two or more, then I use a simple jig and, as I said before, leave the machine in a known position if I have to switch off and return to it next day.
It would be interesting to determine the increased accuracy with a dual sensor set. I would guess that it would not be significant for most home built machines.
What do the big boys, like HAAS, do?
this forum is changing case - wtf !!!Quote:
Originally Posted by magicniner