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croy
30-07-2011, 05:50 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, 06:37 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 john@stevenson-engineers.co.uk

Jonathan
30-07-2011, 08:09 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, 08:37 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, 08:42 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, 09:34 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, 09:40 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, 10:06 PM
actually the components i have used are rated at 80kHz, i am just being cutious.

John S
17-08-2011, 10:24 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, 11:05 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, 08:50 AM
Croy are you meaning to produce these in numbers, or produce a one-off batch for interested parties, or just supplying schematic details?