Hello,
I believe this is my first post on the forum so excuse my lack of terminology.
I work in the mobile hydraulics field, and a particular product we sell is a proportional electro-hydraulic valve. DC voltage only, 12 or 24vdc
The electronic solenoid is a ratio-metric voltage controlled circuit. It has a 25%-50%-75% actuation signal. This means @ 25% supply voltage, I will get full spool travel in one direction, 50% puts my spool in neutral, 75% provides full spool travel in the opposite direction. Simple so far right?
Well, the solenoid has fault monitoring so that if the voltage drops below the 25% or above the 75% (there is a +/- margin) it will shut the coil down for safety.
To make an 'at home' controller for this coil, the manufacturer recommends a 500ohm resistor on +, 1K pot, 500 ohm resistor on ground. This all makes sense to me at this point, after some considerable reading. This works fantastic on my 12vdc power supply. However, I only have a 10K pot, so I substitute this with a 5k resistor, 10k port, 5k resistor. On the power supply, still works fine. However, when I plug it into my 'PVE' (coil) it drops 2+ volts, immediately when my pot is all the way up. This drop in voltage prevents full spool travel. Then I read (in the part book)the coil has 12K impeadance. Then I read (online in various places)and it says that your output current should be 10% of the input current, which leads me to believe that is why the manufacturer specifically said 1k pot vs. any ratio available.
Does this make sense to anyone who can break it down? I prefer stupid terms, however the more technical you can get on voltage dividing and impeadance, the better. I found some great sites online
http://www.sengpielaudio.com/calculator-voltagedivider.htm
And then use the www.falstad.com/circuit/ to check things out, and it sounds like I need to drop my pot down to a 1K, but wanted to get some education on the subject.
I am fascinated with electronics and I look forward to your kind replies.
Thank you!
I believe this is my first post on the forum so excuse my lack of terminology.
I work in the mobile hydraulics field, and a particular product we sell is a proportional electro-hydraulic valve. DC voltage only, 12 or 24vdc
The electronic solenoid is a ratio-metric voltage controlled circuit. It has a 25%-50%-75% actuation signal. This means @ 25% supply voltage, I will get full spool travel in one direction, 50% puts my spool in neutral, 75% provides full spool travel in the opposite direction. Simple so far right?
Well, the solenoid has fault monitoring so that if the voltage drops below the 25% or above the 75% (there is a +/- margin) it will shut the coil down for safety.
To make an 'at home' controller for this coil, the manufacturer recommends a 500ohm resistor on +, 1K pot, 500 ohm resistor on ground. This all makes sense to me at this point, after some considerable reading. This works fantastic on my 12vdc power supply. However, I only have a 10K pot, so I substitute this with a 5k resistor, 10k port, 5k resistor. On the power supply, still works fine. However, when I plug it into my 'PVE' (coil) it drops 2+ volts, immediately when my pot is all the way up. This drop in voltage prevents full spool travel. Then I read (in the part book)the coil has 12K impeadance. Then I read (online in various places)and it says that your output current should be 10% of the input current, which leads me to believe that is why the manufacturer specifically said 1k pot vs. any ratio available.
Does this make sense to anyone who can break it down? I prefer stupid terms, however the more technical you can get on voltage dividing and impeadance, the better. I found some great sites online
http://www.sengpielaudio.com/calculator-voltagedivider.htm
And then use the www.falstad.com/circuit/ to check things out, and it sounds like I need to drop my pot down to a 1K, but wanted to get some education on the subject.
I am fascinated with electronics and I look forward to your kind replies.
Thank you!