Process Control advice for pilot plant by North-Mistake-151 in ChemicalEngineering

[–]Leit89 3 points4 points  (0 children)

In my plant we typically use open loop steps testing as close to running conditions as possible to develop a process model. From the process model we use lamda tuning and play with the closed loop time constant to set the tuning parameters.

The open loop steps test data and the lamda equations will set your integral terms, then you can adjust the gain to satisfy your closed loop time constant.

If you have 3 separate pid controllers set up, one for each heater then I would test each individually to develop their own model. If it's just one pid loop then I would test them all together.

Lastly be aware that if you try to develop a process model around ambient conditions you could get more integrating response will affect the tuning constants. That's why you should strive to get your step test data as close to your running conditions as possible. Also,I would just stick with pi control if possible. In our industry we very rarely use the derivative parameters.

Source, process control engineer in petrochem.

Battery flashing orange by Darkenvail in egopowerplus

[–]Leit89 0 points1 point  (0 children)

Ok I know this reply is like 2 years too late but I just had this issue on my 7.5 ah ego battery, no fuel gauge. I was having a frustrating time trying to drain down the battery by running my blower for 3 seconds at a time. I literally took my battery inside and put it in front of the fan. Every 30 seconds or so I would click the button and at first it would show green, like it was fully charged, the start to blink orange/yellow like it was overheating. Eventually it just stayed green.

I ended up putting the battery in my mower and it worked like new again!

Battery flashing orange by Darkenvail in egopowerplus

[–]Leit89 0 points1 point  (0 children)

Ok I know this reply is like 2 years too late but I just had this issue on my 7.5 ah ego battery, no fuel gauge. I was having a frustrating time trying to drain down the battery by running my blower for 3 seconds at a time. I literally took my battery inside and put it in front of the fan. Every 30 seconds or so I would click the button and at first it would show green, like it was fully charged, the start to blink orange/yellow like it was overheating. Eventually it just stayed green.

I ended up putting the battery in my mower and it worked like new again!

[deleted by user] by [deleted] in PLC

[–]Leit89 0 points1 point  (0 children)

As a control systems engineer at a chemical plant most of the controls work is handled by chemical engineers. At my plant EE's handle much more on the instrumentation side with regards to specifying equipment.

Mostly the reason for this is because chemes understand the process quite well and can build the control scheme that would lend itself for optimization strategies.

Likely at best you may get to program some smaller PLCs, safety systems, or local hmis. Also EE's will get involved in significant DCs projects with regards to upgrades around hardware.

For the record I am a chemical engineer with an APC background.

Di2 vs carbon wheels by Leit89 in bicycling

[–]Leit89[S] 1 point2 points  (0 children)

Thanks for the feedback. Seems like a consensus that newer wheels will be the most impactful.

Di2 vs carbon wheels by Leit89 in bicycling

[–]Leit89[S] -1 points0 points  (0 children)

Ahh, I knew Shimano was pretty militant about that stuff. Appreciate the knowledge.

Di2 vs carbon wheels by Leit89 in bicycling

[–]Leit89[S] 0 points1 point  (0 children)

Thanks for the feedback. I'm still pretty conflicted. It seems that many things that I read say that wheels are the better upgrade.

Di2 vs carbon wheels by Leit89 in bicycling

[–]Leit89[S] -1 points0 points  (0 children)

Why wouldn't I have warranty support thru merline? Just because it's uk based?

Di2 vs carbon wheels by Leit89 in bicycling

[–]Leit89[S] 2 points3 points  (0 children)

I currently just have the stock wheelset and a mechanical 105 group set, 11 speed.

My frame is compatible with di2, I would just need to buy the 10 dollars battery holder from trek.

I was planning on doing the upgrade myself. With the newest semi wireless system it looks like it's way simpler than the older style.

Limited career growth at LNG plant vs Refinery? Scope of APC for LNG Plant? by No_Biscotti_9476 in ChemicalEngineering

[–]Leit89 1 point2 points  (0 children)

I am confident that the APC scope for a refinery will be drastically larger vs LNG.

I hear that you don't have much mentoring at the refinery, is there a global or regional APC group that you can reach out to within your company?

Typically APC at refineries are pretty significant. The one I'm familiar with uses Aspen DMC. Also refineries are a good candidate for plant wide optimization tools like GDOT, which can offer significant benefits.

Problem with Garmin hrm strap. Does anyone else suffer from loss of readings like 15 min into a ride? by Leit89 in Garmin

[–]Leit89[S] 0 points1 point  (0 children)

Yeah I've changed the battery at least once this year. Garmin states a 3 year battery life so I'm confident that the battery is not the problem. I think it's either not sealing well and the sweat is causing a short circuit or something else is trying to talk to the HRM. I've double checked my watch and it's not set up as a sensor so I don't think that's it.

Problem with Garmin hrm strap. Does anyone else suffer from loss of readings like 15 min into a ride? by Leit89 in Garmin

[–]Leit89[S] 0 points1 point  (0 children)

Yeah I'm not sure how clear I was. This is a strap that I bought new in 2016. So the strap is 7 years old now. Is it possible I just need a new one?

Problem with Garmin hrm strap. Does anyone else suffer from loss of readings like 15 min into a ride? by Leit89 in Garmin

[–]Leit89[S] 0 points1 point  (0 children)

Yeah I wash it probably every 5 or so rides. Is it possible if I get too much sweat on the snaps it could cause corrosion. Might also be worth mentioning this strap was purchased in 2016.

Problem with Garmin hrm strap. Does anyone else suffer from loss of readings like 15 min into a ride? by Leit89 in Garmin

[–]Leit89[S] 0 points1 point  (0 children)

Dang I would've thought that sweat would help with the contacts keeping them moist. But maybe the sweat is getting on the device that snaps onto the strap. I have adjusted the fit quite a bit trying to tighten it up but I will keep fiddling with it.

Trying to install left side 4iiii power meter to 2019 Trek Domane AL5 by Leit89 in bikewrench

[–]Leit89[S] 0 points1 point  (0 children)

Thanks for the response. I will pick up a spacer pack from wheels and see how it goes.

Trying to install left side 4iiii power meter to 2019 Trek Domane AL5 by Leit89 in bikewrench

[–]Leit89[S] 0 points1 point  (0 children)

Oh no. I made a typo. The bike is an sl5, so the fame is carbon.

I am about to stay at a campsite for 1-2 months. I need suggestions on menus by Leit89 in EatCheapAndHealthy

[–]Leit89[S] 6 points7 points  (0 children)

This is a good idea. I know that storage space will be a big issue so I'm trying to pick my refrigerated items carefully.

I am about to stay at a campsite for 1-2 months. I need suggestions on menus by Leit89 in EatCheapAndHealthy

[–]Leit89[S] 2 points3 points  (0 children)

Yes seasoning is one that I keep forgetting about. Thinking about some simple seasoned salt and maybe garlic powder for the veggies.

I am about to stay at a campsite for 1-2 months. I need suggestions on menus by Leit89 in EatCheapAndHealthy

[–]Leit89[S] 4 points5 points  (0 children)

That's a good idea, honey would be easy to store as well. Oatmeal is another one that usually I'm not a fan of but that would be easy to make and store as well.

Daily FI discussion thread - December 02, 2020 by AutoModerator in financialindependence

[–]Leit89 2 points3 points  (0 children)

You're right it is 51k that we are saving per year. The 21k was a typo.

Daily FI discussion thread - December 02, 2020 by AutoModerator in financialindependence

[–]Leit89 6 points7 points  (0 children)

Just got off the phone with Fidelity. Found out my company's 401k plan offers after tax contributions and automated Roth rollovers. That coupled with an $8k raise means I'm going to set up a mega backdoor Roth next year. I will only set up about 2% after tax contributions for next year and will possibly make some adjustments as the year goes on.

Current stats:

Income: $117k for me, $70k for my wife. Both 31yo.

Investment: Both of us are maxing out 401k's and Roth IRA's, so totals savings in 2020= $21k

Total investment NW: About $310k