Lol.

A1/A2 will be your coil and is energised by the control circuit as my previous post............voltage needs to be checked as it could be a 230v or a 415v coil and that would be your control circuit voltage so you don't really want to be taking that to your lid switch:)

or 110v ac...
 
i always use schiender xps 2 wire control safety relay... pretty easy to wire really ! but of course be aware whatever your control voltage this needs to be the same (i.e) 24vdc, 48vac, 110vac, 230vac, 400vac?

you have a reset pb.. and connect all your outgoing control wires to the bottom of this so when you hit the e-stop it kills everything in the panel hope this helps regards
Buy Safety Relays XPSAC emergency stop relay,110Vac 3NO Telemecanique XPSAC3421 online from RS for next day delivery.
 
you basically feed your control lines (generally 2) in most basic start stop circuits, connect the stop relay coil (a1 + a2) through the stop button so that when you hit e-stop it will kill all control (with the estop being n/c contact) and also take the 2 control wires which come into the bottom of the esr through the estop they are really easy to wire up !

ensure the esr is protected on the incoming and outgoing sides of the supply i.e 2a circuit breaker or less!!
could you not just use the old fashioned NVR Coil?
 
We use safety PLC here now. There are lots of safety relays and I suppose it depends on what category of stop you require as to which type of relay you use.
This all depends on the risk assessment that should be done on the mixer (if you are upgrading the mixer to current regs).
But if what Tony says is true for your mixer and that the motor will stop straight away when the lid is lifted then there may be no need for a safety relay.. All depends on the risk assessment mate.

Paddle mixers depending on the product plasticity will normally stop dead IF LOADED.
Unloaded they will run on.

This is where common sense has to play its card.
Most of my work has involved centrifugal fans up to 2500HP. Are you going to try to stop that quick?

No amount of safety relays can take out kinetic energy. 20 minutes for a 2000HP fan to stop due to the fan impellor acting as a flywheel.
 
Paddle mixers depending on the product plasticity will normally stop dead IF LOADED.
Unloaded they will run on.

This is where common sense has to play its card.
Most of my work has involved centrifugal fans up to 2500HP. Are you going to try to stop that quick?

No amount of safety relays can take out kinetic energy. 20 minutes for a 2000HP fan to stop due to the fan impellor acting as a flywheel.

As you say Tony, you have worked with these mixers before. I haven't. Common sense works with most people but not all and unfortunately you have to allow for the thicko's who want to put their hands into things and press buttons for no reason.
If I was to put my name down on the re-design of this mixer I would use a locking solenoid on the lid and monitor to see is the mixer is still moving. I'd keep the lid locked until the mixer stops.
Just out of curiosity, how to the modern mixers work? Do they lock the lid while the mixer is moving?

Regarding the fans, don't they have guards to stop people touching the fans with their hands?
 
... this mixer is a heap of gypsy waste and needs to be cut into manageable pieces of scrap so it can be carefully loaded onto their flat beds when no one is looking at lunch time.

It's not worth my time, materials, or potential swearing to get functional. The shaft is totally off alignment, the gear box is on its last legs, the bearings are about as smooth as Brian Blessed's chin and the pneumatics leak more than a pensioners underpants.

Sooner is finds itself smelted down to make tea spoons the better.
 
So, all in all, your having a fab time.....
 
Let me find the right little smiley thing to emulate my exact expression.................................










:furious3::13::censored:




Oh look i found a few
 
Wade... don't wire it to that drawing in post #34, else it could start without pressing start!
 
230v control is what was present on the machine already. is 230v control a problem, or just not ideal? And if so, Tony how would i generate a 24v DC supply voltage from a three phase incoming supply? Would i need a DIN mountable transformer or something to generate my 24v control for the switches or is there something else. Been looking through RS but frankly not sure what im looking for.
 
But i still need a 24V supply..... im going a little mad....and talking to myself at my desk....why is there a penguin under my desk? Who stole my electric wok......why can't i breath properly.
 
How?

The starter has to be reset.

If this is in response to post#50 {wrt post #34} then the wire from 13 and linked from L3 (if I'm reading Wade's schem. correctly) goes to the unswitched side of the start contact, through the stop and pressure switch to A2 thus powering the coil if the pressure switch is/becomes closed!

I'm humble enough to be corrected though.
 
230v control is what was present on the machine already. is 230v control a problem, or just not ideal? And if so, Tony how would i generate a 24v DC supply voltage from a three phase incoming supply? Would i need a DIN mountable transformer or something to generate my 24v control for the switches or is there something else. Been looking through RS but frankly not sure what im looking for.

The schematic shows the control wired across 2 phases mate hence 415v not 230v :)

edit.
That's an old drawing and not relevant here I gather..........soz :)
 
With my eyesight i can hardly make anything out on that drawing. But it seems it's the wrong drawing.

WADE!
 
You know they give us all a laugh, so why not...

Hows the Risk Assessment coming along?
Dont take this the wrong way mate, but I hope you do the design fully before you purchase any components.
 
The risk assessment currently says:

Ribbon Blender Operation

Who is at risk: Ben
What are the hazards: Ben
Evaluate the risks: Ben might die
Recorded findings: Ben is dead
Risk assessment review: It's a shame Ben is dead
 
Alright Spoon, you've made your bed mate.....

haha Am I coming across like an annoying s#*t??? Im good at that..... Dont really mean to....
 
Wade over time it’s been obvious you can’t/won’t grasp the safety aspect of plant control.

Just remember if someone gets hurt it’s you’re neck on the block. The HSE are very good at swinging the axe.
They tried to get me, I was facing criminal and civil charges. I was totally exonerated but I went through hell in the process.
 
Wade over time it’s been obvious you can’t/won’t grasp the safety aspect of plant control.

Just remember if someone gets hurt it’s you’re neck on the block. The HSE are very good at swinging the axe.
They tried to get me, I was facing criminal and civil charges. I was totally exonerated but I went through hell in the process.

Just look at a TV near you " Have you been injured........................"
 
Wade over time it’s been obvious you can’t/won’t grasp the safety aspect of plant control.

Just remember if someone gets hurt it’s you’re neck on the block. The HSE are very good at swinging the axe.
They tried to get me, I was facing criminal and civil charges. I was totally exonerated but I went through hell in the process.

No Tony youre right I wont grasp it by just expecting to learn all i can from this forum. I need to seek professional tuition and spend some time with someone watching how they worl and getting stuck into some solid theory... I don't expect to be competent in such matters after a couple of hours spent sat here talking to you lot.

But

I enjoy coming here, to ask the questions i am unsure of and to generate discussion around these points to facilitate my understanding, albeit maybe slowly and not very efficiently, however i feel it is useful nonetheless.

Control is not something i do much of, but have the potential to do lots of, i also, contrary to your opinion have the potential and capacity to learn given the right circumstances, what i need to in order to be more than capable to overcome the tasks presented to me here.

Not taking my bat home at all and I fully understanding the implications of making a cock up and someone getting hurt, but i feel it is better to ask the questions, rather than blundering on ahead with it.

I can/will grasp the safety aspect on plant control, after all, if you managed it, im perfectly sure i can. I have discussed with my seniors here sending me away on a control and automation course to aid the beginning of my learning curve, hopefully then, i wont have to waste your time replying to my threads mate. I have had zero face to face help with plant control, i have managed to learn what i can from advice given on this forum, and will continue to do so. It is, after all, what it is for.
 
Much as I’d like an apprentice again I’m now too ill to work. BUT I will help you where I can.

I had to accept change from the simple control of 40 years back to take on board the changes in legislation. You are now constrained by that legislation from the outset.

Modifying a basic starter becomes embroiled in red tape. The stupid thing is, nothing in the basics has changed, its just more complicated.

I spent time in R&D with a totally lunatic production engineer. I had a notice above my desk, “I’m looking for ways to stop it!” He wanted everything speeding up.

Stopping a plant safely is the prime directive.

Some plant designs I’ve done where massive centrifuges were used, part of the program would short out all the safety interlocks. Overloads, thermisters, et al all bridged out by the program. It didn’t matter if the motor was on fire, it had to keep running! If someone was wrapped up in it, their dead long before anything can be done about it.*
For it to start its cycle everything had to be in place.
It would be too dangerous to stop the machine without it going in to a controlled emergency shutdown mode. Shut down took time but it stopped as quick as I could get it to do so safely without endangering the other workers.
The original design had an E-Stop, it just cut the power and it drifted to a stop. My set up the centrifuge went in to regenerative braking but only if the temperature in the centrifuge made it safe to do so. The first thing that would happen is three X 150HP water pumps would kick in to cool the centrifuge shell. The temperature in the centrifuge could be 1300°C

*HV work, one question you get asked is “what do you do if someone receives a HV shock?”
The answer is callous, “assume they are dead!”
The safety of the living is more important!

Have sent you a PM.
 
Much as I’d like an apprentice again I’m now too ill to work. BUT I will help you where I can.

I had to accept change from the simple control of 40 years back to take on board the changes in legislation. You are now constrained by that legislation from the outset.

Modifying a basic starter becomes embroiled in red tape. The stupid thing is, nothing in the basics has changed, its just more complicated.

I spent time in R&D with a totally lunatic production engineer. I had a notice above my desk, “I’m looking for ways to stop it!” He wanted everything speeding up.

Stopping a plant safely is the prime directive.

Some plant designs I’ve done where massive centrifuges were used, part of the program would short out all the safety interlocks. Overloads, thermisters, et al all bridged out by the program. It didn’t matter if the motor was on fire, it had to keep running! If someone was wrapped up in it, their dead long before anything can be done about it.*
For it to start its cycle everything had to be in place.
It would be too dangerous to stop the machine without it going in to a controlled emergency shutdown mode. Shut down took time but it stopped as quick as I could get it to do so safely without endangering the other workers.
The original design had an E-Stop, it just cut the power and it drifted to a stop. My set up the centrifuge went in to regenerative braking but only if the temperature in the centrifuge made it safe to do so. The first thing that would happen is three X 150HP water pumps would kick in to cool the centrifuge shell. The temperature in the centrifuge could be 1300°C

*HV work, one question you get asked is “what do you do if someone receives a HV shock?”
The answer is callous, “assume they are dead!”
The safety of the living is more important!

Have sent you a PM.


FFS, no wonder you are ill , thought we had it rough.
 

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DOL starter 7.5HP, 3 ph motor
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