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Kirk Fraser
- 11th March 2011, 06:43
I've been trying to get a proportional control for a hydraulic valve working on another brand of microcontroller for a long time. So instead of posting my failure(s) for analysis, I thought asking for a circuit i haven't seen before might be better. Where would I find such a circuit? Thank you.

cncmachineguy
- 11th March 2011, 14:15
It would help if you can tell us what type of valve it is and how it is controlled. ie. a cartriage valve with a coil you want to modulate or a "smart" valve with built in controller that needs a 0-10V position siginal

Kirk Fraser
- 12th March 2011, 00:33
Here's the data sheet for the hydraulic valve (or very close to it, the actual valve has 2 coils for 3 way, center off, operation). http://www.sterling-hydraulics.com/files/pdf/JP04C31.pdf
The voltage for each coil is 24 VDC at 14W-18W so I've been trying to make a 1A chip, IRL530 work to provide proportional control.

It doesn't come with electronics, just the coils. My understanding is it operates A0-24V B0-24V where the coil energized affects direction and voltage affects rate of flow.

aratti
- 12th March 2011, 06:53
From the diagram it seems the valve will produce a linear flow function from 20% to 60% of the rated current. You can use a PWM to obtain the desired flow control.

The attached schematic has been designed to control the speed of a motor but it will be OK also for this proportional flow valve.

Cheers

Al.