Let the fun begin !!! ???

[PAULRO]

cheers for the driver info. i had calculated for 5 motors even though i will only use 4 for the time being . the 5 will draw 13.2 amps @70 vdc hence the 750 VA.
The 625 VA delivers 11.90 amps. i hope my calcs are correct! is there a way around the in rush of current?

[JAZZCNC]

is there a way around the in rush of current?

Yes Don't turn it ON. . .

You can build an inrush circuit using resistors, thermisters etc but I prefer to avoid this and use smallest transformer possible and then use a C or D rated fuse if still trips which I rarely do upto 625va. Can use slow blow fuses as well.

To be honest I very much doubt you'll ever run 5 Motors at same time that pull full amps at same time so I'd still go with 625Va and 12A.

[IanS1]

As all 5 motors won't be drawing maximum current at the same time, allowing for around 70% of the total quoted current draw should be plenty.

[PAULRO]

625 VA it is then ! every day is a day for learning.

[PAULRO]

so i need 4 drivers EM806 a break out board and a smooth stepper. can anyone recommend a smooth stepper and a breakout board that's compatible with the drivers and where's the best place to purchase ?

[EddyCurrent]

so i need 4 drivers EM806 a break out board and a smooth stepper. can anyone recommend a smooth stepper and a breakout board that's compatible with the drivers and where's the best place to purchase ?

Smooth Stepper is the name of a particular motion controller, it's not a generic name. http://www.amadeal.co.uk/acatalog/Pa...cessories.html
There are alternatives to the smooth stepper, have a read here; http://www.mycncuk.com/threads/7718-Usb-smooth-stepper some have the breakout board built in I think.

[PAULRO]

I have the PLCM-E3 motion control & PLC4X-G2 breakout board ordered but they will not be with me until march because of Chinese new year. i am using the time to try and get to grips with the electrics / electronics and hopefully start into the MACH 3 (getting to know you period !!) i know some builders on here do not use bleed resistors to drain the caps from the power supply . i was going to leave the drives drain the caps as suggested on various posts but on second thought said i would at least try and get to understand how it done and maybe use a bleed resistor across the n/c contact of the e/ stop relay to keep to good practice and safety as pointed out. i came across this https://www.digikey.com/document-red...calculator.xls i have a result of 1000 ohms over 35 seconds with initial power at 4.9 watts. OR 1710 ohms for 60 seconds with initial power of 2.8 watts. i don't know if these resistors are viable because i've absolutely no prior experience to work from. maybe they will do or perhaps previous builders use a different spec. i have also updated my electrical dwg to reflect my proposed capacitor bleed arrangement. any feedback on this will once again be greatly appreciated.

[EddyCurrent]

I like this better;



The way you had it created a short circuit across the 70v DC, only relying on speed of operation of the relay to remove it.

[PAULRO]

Cheers Eddy, i'll update that . the older i get the more cautious i'm becoming just as well i put it up for a critique.