Help required MicroLogix 1000 wiring diagram

[Duke55 0]

Hi, PLC noob here. I am a mechanical engineering apprentice serving my time with a well known global company, as part of my apprentiship I have to do some electrical training. My boss has assigned me a smalll project to carry out within my current sector which is a PLC controlled filter element disposal chute from a second floor level dropping into a bin outside. The whole system has now been constructed and is in place, all my electrical components have been installed but before I can go any further I need a wring diagram that needs be checked and verified before I can start to wire up the system. Now being honest I am very unsure of how to do this as my electrical knowledge is still quite weak. I have a MicroLogix 1000 16 bit PLC here that is going to control the system, the PLC program has still yet to be written as I need to get the hard wiring diagram sorted first. The system consists of the PLC being fed from a 110v AC supply with 3 inputs. 2 Allen Bradley guard locks which I have mounted to the bin so it is locked in position during disposal, and a guardmaster trojan 5 safety switch which is mounted on the bin lid so the plc will know when the bin is open so disposal can take place. There are 7 outputs (I think these should be outputs. Componenets are needed in the system whether they are all outputs I'm not 100%). The first 3 which can all be fed off the same output are 2 xenon beacons and a small green light. Although the 2 beacons need supplied using a 24v DC power supply, I have mounted this in the enclosure already along with the PLC itself and a junction box. The DC power supply is an omron 282k-01524. The other 4 outputs are another guardlock like the 2 mounted on the bin, an electromagnetic lock and 2 small lights, white and red, I have got the standard wiring template for the PLC off the AllenBradley website it is on a pdf file, although it is like reading double dutch to me I was just hoping that someone on here could help me get this sorted or even show me an example similar that I could work from. I would even be willing to pay a fee to someone on here to do the drawing for me and email it to me or something. Any help appreciated!

[Duke55 0]

Wiring diagram template can be found in this link. Sorry can't copy and paste the pic from a pdf file. Found in section 2 - wiring your controller. The title is 1761-L16AWA Wiring Diagram. I just don't know how my inputs and outputs should look with regards to this diagram, I am not even sure if they should be N/O or N/C contacts. Or maybe some should have both contacts wired? Edited 27 Feb 2012 by Duke55

[JRoss 84]

Start by writing a sequence of operation. What exactly is supposed to happen when? That will be invaluable for writing the code. Keep it clear and concise, but try to consider all possibilities.

[Duke55 0]

This is the sequence of operations that will happen during the systems operation, the top of the chute has a metal box with a door that is opened via a guardlock for disposal to be carried out. 1) No bin in place, no lid open. 2) Small red light on enclosure energised, box door locked via guard lock. 3) Bin pushed into guard locks and locked into place automatically, lid still closed. 4) Red light on enclosure de-energised and white light energised, box door still locked as lid not open. 5) Bin lid opened and rested on bracket. 6) Magnet closes N/O contacts within safety switch. 7) White light on enclosure de-energised and green light energised. 8) Guard lock on box door de-energised and door can now be opened for disposal. 9) Electromagnetic lock on wall energised to allow box door to be held open during disposal. 10) Two 24v DC xenon beacons energised one upstairs on enclosure and one outside beside bin. These will flash throughout disposal to warn anyone in the surrounding area that filter elements are being dropped down the chute into the bin. 11) Disposal carried out. 12) Disposal finished, ready to evacuate bin and re-set system. 13) Bin lid magnet lifted off safety switch re-opening N/O contacts. 14) Green light on the enclosure de-energised along with the two flashing beacons. 15) Electromagnetic door lock de-energises, spring hinge on box pulls door closed. 16) Box guard lock energised locking door in place once closed by spring hinge. 17) White light on enclosure illuminated as bin still in place. 18) 2 Guard locks on bin de-energised allowing bin to be wheeled away for emptying. 19) White light de-energised, red light energised. 20) System left on stand by until next disposal takes place (4-6 months) To be controlled using Allen Bradley ML1000 PLC; 3 Inputs • Guard lock on bin (2 off) • Safety switch for bin lid 7 Outputs • Guard lock on box door • Electromagnet to hold box door open • Xenon flashing beacon (2 off) • Red light on enclosure • White light on enclosure • Green light on enclosure Edited 27 Feb 2012 by Duke55

[JRoss 84]

Comments/Question: What senses the presence of the bin to start the process? Looks like you also need outputs to energize the bin guard locks. Is the bin door opening by hand, or is that also automated? Is the disposal carried out by hand, or is that also automated? Is there any way to abort the process? This is a basic sequence. Pick an internal integer to act as the sequence step number. Use comparison statements (EQU, NEQ, LIM, etc.) to energize the outputs during the appropriate steps. Use MOV instructions to advance the sequence with the appropriate conditions. I'm sure there are lots of samples of this sort of thing, but let us know if you have difficulty finding something appropriate.

[gbradley 0]

Lots of good information gathered here if you need to see what Electrical symbols look like. http://www.patchn.com Your devices may draw too much power to be driven straight off the PLC Outputs. You will probably need some relays to actuate the magnets and locks. 700-HA32A1 or EQ.

[Duke55 0]

[*]The bin is not sensed, it is manually wheeled into the guard locks, I have mounted the 2 tabs that locate into the guardlocks them self on the bin. Once pushed in they will lock and I figured this could send a signal to the PLC to operate the light on enclosure to change from red to white. [*]Yes the bin lid is opened by hand and rested onto the chute pipe to hold it open. I have fabricated and fitted a bracket that holds the safety switch in place. The magnet part of the switch is then mounted on the underside of the bin lid. When the lid is lowered onto the chute pipe the switch is then made. I thought this could then send a signal to the PLC to trigger the outputs listed in my step sequence above. [*] Yes disposal is carried out by hand. [*] I was hoping that lifting the lid away from the switch when disposal was finished that the system could be worked in a way that this would abort and unlock the bin, re-set the process basically. To be honest this is really small time s%#t than what I'm sure you guys do on a daily basis and I appreciate the time that has been taken to help this far. I'm just really out of my depth with this!

[JRoss 84]

Sounds like you've got the process fairly well thought out. Now to lay it out in code. As long as you have a complete I/O list, you don't necessarily need to wait until you have the drawings to start the program. Start putting something together and post it here, and we'd be glad to review it for you. To elucidate my brief description about the sequence approach, there's a sample snippet of code attached. Sequence.RSS

[Duke55 0]

Thanks for that, appreciate it. With regards to the program the criteria that I need to achieve in this project is set out as such that the wiring diagram needs to come first and be verified as safe and appropriate. Once that is completed then I can wire the components in accordance with my wiring diagram. After this stage then a program will be written and downloaded to the PLC. I will definitely be posting my attempts at the program up here when the time comes. Does anyone have an example wiring diagram they could post up here of a 110 supply feeding a PLC with various I/O's? If I had an example to get the ball rolling then I believe it would be a massive help. I know from reading on here it is encouraged more to make an attempt yourself then people will be willing to help but I just don't know where to start with this really.

[Duke55 0]

Ok built up the confidence and got stuck in myself, think I've made a very good attempt. Will post up the circuit later when I get home!

[OkiePC 14]

I have one ML1000 running as basically a pump alternator, so there's not much here, but I am going to post the wiring I snipped from that with a couple of mods (I added three relays since in the original drawing those were remote references on another page.) EDIT: Ignore the breaker current ratings...that was an unintentional result of my hasty copy and paste job in Autocad. Edited 28 Feb 2012 by OkiePC