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croy
30-07-2011, 04:50 PM
Hi to all,

I am looking to make a breakout board with full opto-isolation on Outputs and Inputs as well as 2x dedicated 10A relays.

The uses will be able to select from a further combination of;
a) 2 out of 3 comprising 1x 10A relay, Charge pump and 0-10V for Spindle control.
b) Channel Y Step and Dir or Chan Y Step and Relay no4 (10A relay)


i believe this board will adequatly cover Lathe and Milling use.

Who of you would have an interest in using such a board.

John S
30-07-2011, 05:37 PM
Roy, What is needed is a RELIABLE board that can handle 2 relays, charge pump and 0 - 10v
Can't see a need for opto's on motor outputs as most decent drivers are opto'd anyway, what is needed is fast opto's on inputs, especially the one needed for threading.

A lot of the boards out there at the moment are right on the edge as regards design and component choice.
Drop me a line off list [email protected]

Jonathan
30-07-2011, 07:09 PM
It really is not hard to make a reliable breakout board. I designed/made some a few years ago with optoisolation on the I/O since it was before I got the isolated drivers. Simple to not have isolation one outputs...

How fast do you need the inputs?

croy
30-07-2011, 07:37 PM
It really is not hard to make a reliable breakout board. I designed/made some a few years ago with optoisolation on the I/O since it was before I got the isolated drivers. Simple to not have isolation one outputs...

How fast do you need the inputs?

still a little uncertain so advice will be grateful. from what i remember, parallel ports struggle much above around 330KHz. unless you know otherwise.

Jonathan
30-07-2011, 07:42 PM
still a little uncertain so advice will be grateful. from what i remember, parallel ports struggle much above around 330KHz. unless you know otherwise.

Thinking about it Kernel speed in mach3 is generally 25kHz, some will run at 35kHz. So ideally you want a bit more than that ... there are plenty of opto-isolators available that run much much faster than that.

croy
17-08-2011, 08:34 PM
My board will be ready in September, for those of you who are interested:

Features:
· Onboard high voltage regulator (70V Max)
· Dual power supplies;
o One 5V DC for the Parallel Port associated logiclevel circuitry.
o One isolated 12V DC to drive port-opto circuitry.
· Integrated Charge Pump for added protection, withoverride jumper for testing.
· Full optical isolation of all inputs.
· Buffered 2x relays, rated at 10 Amps 240V AC.
· The user will be able to select from a further combination of;
a) 2 out of 3 comprising 1x 10A relay, Charge pump and 0-10V for Spindlecontrol.
b) Channel Y Step and Dir or Y Step and Relay no4 (10A relay)
· Opto isolators can handle step signals up to 40 KHz

Jonathan
17-08-2011, 08:40 PM
Good to see that you appear to be doing the isolation properly...more than can be said for some.

You could add an option for a different voltage range for spindle control.

40 kHz is a bit low. Most will only run at 25-35kHz with Mach3, but you can have more and a lot of drivers claim to do 200-300kHz.

croy
17-08-2011, 09:06 PM
actually the components i have used are rated at 80kHz, i am just being cutious.

John S
17-08-2011, 09:24 PM
40 kHz is a bit low. Most will only run at 25-35kHz with Mach3, but you can have more and a lot of drivers claim to do 200-300kHz.

The opto isolation is only on the inputs.
Driver outputs reply on the driver isolation

Jonathan
17-08-2011, 10:05 PM
The opto isolation is only on the inputs.

Ok, didn't realise that as it wasn't stated in the info...40kHz is obviously plenty for the inputs.

Peter.
18-08-2011, 07:50 AM
Croy are you meaning to produce these in numbers, or produce a one-off batch for interested parties, or just supplying schematic details?