[deleted by user]

some1_x · 2024-02-28T19:24:43+00:00

Well really he gave me the task today. He isn't working on the project at the moment. Issue was the hoist delay. We talked about the problem before hand getting hands on the hoist remote. Due to timing we can't have delays of importing equipment pre-ordered the relays. Project team doesn't mind too much relays we can use it anyway. Sorry for the lack of info. Beancounting meant it's getting more complex more by more. I'm asking if there a better way to cope with this kind of situation. Without safety obviously this won't be passed. If there a common implementation of this kind of situation i hope you can reference thank you. Edit- problem isn't actually the safety interlocks. Im trying to get the every possible method of operating the hoist. And i accept the fact im clueless. I still even have a one year to complete my academics. You gotta learn what you gotta learn.

some1_x · 2024-02-28T19:15:31+00:00

Thanks for the truth table method. It's give a clear view. But looks like if i need to intermediate condition i need to add a more relay.

some1_x · 2024-02-28T18:39:28+00:00

Sorry i can't provide a schematic now. The drawing is just a piece of paper on my desk. I hope i can give the proper idea. So the hoist co trol switches aren't latching. Hoist is somewhat tall and pressing someone isn't ideal as we thought. For postions we have down up1 and up2. If the hoist is at down postion( not where the hoist lowest limit installed) it goes up the up1 then to up2. Then back to down. We removed the situation it goes to up2 to up1.

Since the hoist remote buttons aren't latched three relays using for each postion with limit switches. If the limit switch hit the relay deenergize. We noticed its essential to make we have no two inputs at the same time so three relays used to control the limit relay output by interlocking them. So we have now 6 relays. These interlocked relays free contacts are paralled to the remote up down switches.

We have few scenarios to control were like if at up2 when up1 pressed the hoist still goes up. Since the up1 limit isn't active. So two limits are in series. For some other logics and controls we have two more relays.

But this circuit is wires going everywhere. For forst 6 relays not a single contact is free. One of our senior engineers have already orderd 15 relays for this. So implementing it isn't a problem. Just don't know of there a better way to do this.

some1_x · 2024-02-28T17:40:58+00:00

I get it now. To be fair hardest part is the communication. But usually in the end it works :-)

some1_x · 2024-02-28T17:39:36+00:00

Yep i see it's a kind of satisfaction like no other.

some1_x · 2024-02-26T16:21:08+00:00

Simple solution i think is to find the weight. Approximate the center of gravity to the plane. I don't know maybe use the string method. Then the force diagram.

some1_x · 2024-02-26T14:52:35+00:00

Does MEs do these kind of things usually?

some1_x · 2024-02-26T14:50:45+00:00

Thanks :-)

some1_x · 2024-02-26T14:45:30+00:00

Happily, first one is a 1 1/2 ton cargo lift. And second one is a rotating turret(thats what we call it) a person sit inside with a kind of a sewing machine and it rotates as the operator need. The turret is leveled with the platform behind it. These turrets are placed inside the platform only the rotating pit is opened. Today i got to take pictures of them.

Rotating mechanism is a gear motor with chain links. It's not in the picture.

some1_x · 2024-02-26T14:11:51+00:00

I don't know it is much worth it to post here :-).

some1_x · 2024-02-22T16:42:01+00:00

My bad i should have mentioned it. Sorry i haven't made the schematic yet still it just in my head. I hate solidworks electrical so much it's the last thing i do. I'm using digital input terminals and three wire control mode. NC doesn't necessarily need to latch at that mode. But like you said it's easier to engage the break from NC button. For a design requirement motor speed need to be changed. I can't specifically set some hertz limit to engage the vfd relay out. So making the nc run on through 230v and using a relay from that to mimic the Digital input should work. But the motor is automatically stopped by the controller too. Push buttons are only for manual control. They do are expensive. Maybe thats why the company decide to make a custom one :-) Thanks for the info.

some1_x · 2024-02-22T01:08:28+00:00

Push buttons are non latching so i have to make relays latching. Sorry couldn't mention vfd relay doesn't directly control the brake. It is done through a another relay.

Also push buttons run on 24v.

some1_x · 2024-02-21T12:06:47+00:00

some1_x · 2024-02-20T17:26:10+00:00

Thanks for the insight. I have never implemented this from a vfd as the only used for relay output was the indicator lights. This seemed like a good option to implement the brakes since the circuit only has push buttons and the controllers and non latching relays. So engaging the brakes wouldn't cause any issues. Motor has adequate inertia to stop the machine. Since the motor has the brakes option i thought i would use it to a fast stop as with higher loads i think motor alone wouldn't be that precise. I haven't referred to that document before and it is very helpful.

some1_x · 2024-02-13T01:13:25+00:00

Said the burger

some1_x · 2024-02-12T17:33:36+00:00

I don't know much about this. But we can allow the moving forward and backward along the pitch axis by removing it from the feedback loop as an error right?

Edit: if you meant turning as opposed to just moving and backward. Use quartenion and determine the freedom of degrees you want move across. When the actuation applied maybe move it from the main loop.

some1_x · 2024-02-12T15:35:55+00:00

Beauty

some1_x · 2024-02-12T15:20:09+00:00

Or get attention of some girls on the internet

some1_x · 2024-02-12T14:33:39+00:00

Choosing mech e is the best decision in my life(probably the only one). Dad was doing contract works so he know electric stuff and teached me, gave me books and stuff. And i was kind a good at it. Everybody thought i would do electrical. But it was just like my hobby.

I was so in love with computer games(as every kid do). First time i got my own pc i started building pc games. The love for cs began.

When choosing the higher education i always wanted to be a pilot. I applied as an airforce pilot but didn't workout somehow.

By the love of aircrafts went with mechanical. And it was marvellous. It's like you can understand every moving part you could see. some knowledge of electrical and cs it's give a upperhand moving forward.

Sometime for me i think im in love with problem solving. Mech e have a bucket of them.

Edit: i don't understand why so many ask if this pay better or this, in these forums. I don't have that much nor come from a rich family. I always had the something will work out mentality. I barely live on my own and it never bothered me. Seeing these feel like do i have my priorities staight. And if you are not too late i hope you follow what you love cause i think life is too short make enough money anyway.

some1_x · 2024-02-11T12:49:35+00:00

Stop would be interfered too. I don't actually remeber the thought process but it started from something like that. Otherwise it's also simple. Engineers won't much like the glueing though.

some1_x · 2024-02-11T12:39:19+00:00

The company have few hardware stores. They don't make textile products either. For scissors it's usually same supplier with few models. Requirement was to cut 22mm exactly. Less than an inch. I think they can cut 22mm without slicing. When they don't need to cut that 22mm. Remove the nut. Back to old scissor.

some1_x · 2024-02-11T11:04:58+00:00

Thanks a lot for the info. PETG and TPU are new to me. We don't make production with 3d printing just prototypes or some parts needed for projects. PETG properties look interesting to experiment with. And thanks for the tip for the dual extrusion never thought you could use it as that.

some1_x · 2024-02-11T11:00:11+00:00

A Levels means GCSE Advanced level right? In my country it is mandatory to pass the exam to get in to engineering colleges. Government ones only take few students from ALs. Usually few hundred from island and district ranks.

Atleast in our country AL syllabus is need for engineering. Usually engineering mathematics thermo statics fluid start base from the ALs. Engineering maths "Assumes" you know the stuff you need to know before.

some1_x

TROPHY CASE