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To: Diana in Wisconsin

Two days until our third spring which looks like it will lead into our second single day of summer - 80+

Sitting here recovering and will be all day because it’s cold out there. Feeling half way decent this morning.

Been playing around with the Linear Actuator and “logic”. I have no idea how to stop the actuator at a certain % open even though I can see what % open it is. Not sure if there’s a way.

The controller doesn’t know that the % reading has anything to do with the relays that open and close it and I see no way to Extend until a certain reading. It only polls for a reading every 3 seconds so it’s not real-time data.

What I came up with is using Timers which can be created. I know how long the full stroke takes, 56 seconds. Half of that time is 50% - 28 seconds.

I used a built in relay that isn’t used for anything right now as trigger to mimic a wind speed scenario. Turn on relay and the actuator retracts to 0%, a 14 second Timer is set, the actuator extends until the timer runs out. That puts the actuator at 25% extended which would be tunnel side 25% open.

The temp vs wind scenario for 25% open? I still need to come up with those and I’m limited on how many logic entries I can have. Luckily relays can be grouped so one command can control a group of relays. Doesn’t need to be too complex. Closing sides part way will be for protecting the plants and then the tunnel from wind damage.

I may end up writing code for the sides and use the built in GUI tasks page for more basic things.

Oh and I had my math wrong on the actuator speeds. They take 56 seconds for full stroke under no load. Little longer under full load. Think I divided instead of multiply.

and with that, I think it’s nap time. Just suddenly got sleepy.


433 posted on 03/16/2026 10:20:18 AM PDT by Pollard (It's just another few hundred $$$)
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To: Pollard

“I think it’s nap time. Just suddenly got sleepy...”

People say that all the time when they’re talking to me, LOL!


435 posted on 03/16/2026 11:44:05 AM PDT by Diana in Wisconsin (I don't have, 'Hobbies.' I'm developing a robust Post-Apocalyptic skill set.)
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To: Pollard
Been playing around with the Linear Actuator and “logic”. I have no idea how to stop the actuator at a certain % open even though I can see what % open it is. Not sure if there’s a way.

Was actually very easy.

I'm gaining confidence in the readings I get from the actuator as far as what percent open it is. There is no delay in them aside from visually. It will stop dead on the number I tell it to. It just takes up to 3 seconds for the display to catch up. I might not have to worry about retracting fully every time just to Extend it. I was worried about the number getting less accurate with every partial move. Knowing it's accurate will reduce the number of Conditional Tasks I'll need to use. That's good since I'm limited to 50.

Went out and cut the chain off and removed the derailer from that bicycle. That was enough outdoors for me for the day.

452 posted on 03/17/2026 1:44:32 PM PDT by Pollard (It's just another few hundred $$$)
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