How to gain Heavy Industrial and PLC experience

[Timbits]

Hi all,


I have a couple of years post apprenticeship experience mostly in large commercial and medium industrial install but im now looking at how to get into some proper Industrial stuff including gaining PLC/controls experience. Have been trawling many different recruitment agencies and websites but it seems to be the fairly standard 'must have prior experience'. Has anyone done a similar thing or do you have to start from Apprenticeship level in this sort of work? Or if anyone needs a hand in the West Midlands/Warwickshire area I would be more than willing to assist and can send CV/qualifications/contact details if interested.



Many thanks in advance for any help, Steve

 

[johnboy6083]

Im not experienced with PLC's (apart from installing the cabling to them, and panel mods ect), but i got my experience with controls ect from working for the right companies, and asking to get involved.

Im nowhere as involved as say Tony, Darkwood, Silver Foxx ect are, but i understand the basics, i can fault find them and i can install them.

Im now doing a HNC in Electrical Engineering in order to be able to get more involved, and gain more understanding.
Experience is the best way of getting these jobs, but also being keen is another way. Showing an interest is a good thingh for an employer to see.
Good luck mate.

As for heavy industrial jobs, the best way for you to gain experience is to get on an agency who deal with this type of work. Its not easy to get on these jobs, as they pay well, and as soon as people know about them they are massivley over-subscribed.

 

[Knobhead]

I started down the PLC road when the company I worked for decided thats the way for them. We just got dragged along, you either sank of swam.
As John has said, to get in to heavy engineering the agencies seem to be the way.

 

[Timbits]

Johnboy, what format is your HNC, are you doing evenings or Open University? Have been looking at this myself. Also, how are you finding it with regards to fitting it in around work/life and how difficult is the theory?

Thanks again guys really appreciate the help,keep hassling the agencies and carpet bombing the CV it is then!

 

[vaughant]

Shame you can't relocate to Aberdeen,I can get you in my place straight away and they would get you involved with plc's/control straightaway.Best thing is to learn diagrams,learn how they operate as industry depends on it,it's how you find your way around stuff like this

You need to remember a plc is purely a computer for us electricians to understand with pretty pictures of switches instead of '0's and '1's as you find in binary code (although STL in Siemens is basically that) but again it's just generally a way of switching something on or off at its very basic form.Yes this is done usually in a pretty spectacular way with data words,timers,variable tables,AND,OR,NOT gates but again if you can follow electrical drawings and basic principles then you can grasp the basics easily.I'm assuming your young so this is the field to get into,the more technical side of it.The problem you may face is that often you learn this via your apprenticeship so it maybe hard to get out of the blocks a bit to sort pick up on it but it's worth a try.Industrial control has done me well over the years.

 

[Knobhead]

Just to give you an idea of ladder layout.

View attachment 14979

 

[vaughant]

What plc make is that tony?Mitsubishi?Looks a very neat system.

 

[Knobhead]

Telemecanique PL7 Looks even better when your on line :tounge_smile:
I had to learn it after a management cock up, I wanted to us Mitzubishi. They insisted I used a Modicon PLC "everyone understands Modsoft". The new PLC arived and "no one" understood PL7. When the place shut down I was still the only one to understand it.

Used in their STX and in new Modicon's

 

[johnboy6083]

Johnboy, what format is your HNC, are you doing evenings or Open University? Have been looking at this myself. Also, how are you finding it with regards to fitting it in around work/life and how difficult is the theory?

Thanks again guys really appreciate the help,keep hassling the agencies and carpet bombing the CV it is then!

Im doing one day per week. Its costing me a fortune in lost wages (1/5 of my income), especually as ive not long split up with my GF of 7 years.
I really thought i would struggle but so far im doing fine. Calculus isnt as hard as people make out, but there again we have a very good course, and a good tutor.
Im looking forward to finishing it, and maybe go onto foundation degree/HND and then maybe a degree.

 

[Timbits]

Thanks all for the great response, definitely given me some food for thought. Applying for everything and everything at the moment but understandably hard to gain an Industrial start with only one recent relevant (CompEx) job, still sticking with it mind!

Tried to message you Vaughant regarding your work in Aberdeen, as I am in the position of being able to relocate pretty much anywhere and have family in Arboath, however I cant private message until I have reached 15 posts, is there any way of you messaging me? If not will post my e-mail address.


Thanks again for the help, Steve

 

[grantr37]

quite a big post coming up in sections, hope this helps a little bit, any questions please ask



cheers

grantr37

 

[grantr37]

Just to give you an idea of ladder layout.

View attachment 14979

years ago they used to teach in college using ladder diagrams and everything was coded in low level OP code(machine code), hand coded with a great deal more thinking about timers+WDT's, interrupts, jumps, no ops,registers, memory locations, pointers etc.....now everything gets programmed using SDK's (Software Development Kits- AKA compilers) and high level language, usually C, so that a lot of the issues with different PLC chips get ironed out by the use of manufacturer designed programming software tools instead of relying on in depth learning for each new device....the new PLC's and microcontrollers all have inbuilt memory and timers, which the older ones had on a separate card....

In a lot of Colleges they teach this as part of the microelectronics part of the course, and often they never build anything to experiment with the programs but instead run them on a PC based simulator before running on a specially bought in board with Led's to indicate activity/switching and a keypad/LCD for input and information display.....with the students gathering round and taking turns at loading up and demonstrating programs running...usually from a compact flash card or USB memory stick these days....


A lot of Colleges refer to the devices when they teach about them by calling them Microcontrollers and some refer to them as PIC's/PIC Chips (peripheral interface controllers) depending on which manufacturers devices they use there for tinkering about with.....
At University they tend to teach the same but usually add some form of PLC portion as a requirement in projects, referring to them as microcontrollers, if you speak about a PLC they will tell you that this refers to a whole circuit board incorporating a Microcontroller and used in industrial control, then go on about the other interface chips comprising a part of the whole board....



the Integrated circuit chips available these days all have quite a bit of in built memory, and can interface to external memory to load programs stored on them, they can skip to new portions of software from interrupts in the main program that are initiated under certain circumstances and load up/run them from a memory chip on a PCB, a compact flash, a USB memory device or even use handshaking via serial USB interface from a PC/Laptop...
The microcontrollers/PLC's can also check for an externally loaded program by checking ports for communications before loading software stored locally (internally) ie they can check for software updates or to see if an interface cable is connected to the main board, if not available the pre-loaded software/firmware runs instead...



many New models of microcontroller/PLC IC's (Integrated circuits) have inbuilt Digital signal processing (DSP's) that allow for DA/AD conversion, so that analogue signals can be input and digitised then checked/compared to tables of values, then the chip can carry out tasks based on the inputs, and analogue outputs can be produced, such as for example analogue waveforms for passing via an amplifier to a drive unit etc...

 

[grantr37]

PLC= Programmable Logic Controller
PIC= Peripheral Interface Controller
UC=Microchip (with a number this is used to label chip ID's on schematics)
ROM=Read Only Memory
RAM=Random Access Memory
EEPROM=Electronically Erasable Programmable Read Only Memory (can be re-written over and over but is non-volatile)
RAMDAC= Random Access Memory Digital to Analogue Converter
D/A= Digital to Analogue Converter.
A/D= Analogue to Digital Converter.
DSP=Digital signal Processor
N/O= Normally open
N/C= Normally closed.
Bootstrap= small package of software run at first start up of a device in order to load other software and settings.
BIOS= Basic Input Output System
FLASH RAM= High speed Strobeable rewriteable memory.
Strobe= writing and re writing of memory locations, usually referred to when high speed temporary use of memory occurs when variables (internal values stored such as readings from sensors) change regularly.
Clock (CLK)= INTERNAL CLOCK, sometimes referred to if there is an external clock (timebase) as well
WDT= Watchdog timer, this is the internal timer that the software uses to time operations/tasks.
K=count (eg K1000 = 1 second )
JMP=Jump
NOP=No Op (no operation)
BIST= Built in Self Test


SSROM= Single Shot ROM (once only, make a mistake loading software and its the bin) only used now in military equipment and manufactured to order, not for sale...
EPROM=the same as SSROM (Electronically Programmable Read Only Memory) this is single use as well, very rare now...
UV EPROM= Ultraviolet Erasable Programmable Read Only memory, very rare now, used to be the standard before EEPROM was first invented, then it was phased out after about 2001 when re-usable memory bacame very cheap(this could be erased by putting it in a UV light box the same as those used for fixing ink on Printed Circuit Boards before etching) you may come accross this in contol boards on older Lifts/Elevators and in Fire Alarm Panels, BEWARE, don't peel off the sticker as you will probably wipe the program in daylight(corrupt it) and will have a hard time getting a replacement modern one written up with the correct software at short notice...

FPGA= Field Programmable Gate Array

UVEEPROM erasing worked by ionising the small amount of gas sealed in the optical chamber (little window) which made the whole platter conductive and wiped the static charge off of the memory surface, resulting in all the cells/locations being wiped off and becoming 0's instead of a series of appropriate 1's and 0's that were loaded on when written...

EEPROM can be re-written over and over pretty much indefinately and is what is inside all modern controller IC's, this is wiped by strobing all memory locations to 0 or (0FFFFX) and then loading in new values...


Many years ago (from early 1970's to about 1988) a lot of programs were etched into the IC strata (the semiconductor structure) at the factory by using optical etching, this was permanent, and interestingly this type of memory is solidly permanent and can not be wiped by an electromagnetic pulse as it is "burned in"....there is a lot of effort involved to do this though...

The old system of using a program stored on a separate chip soldered or socketted onto the board is pretty much non-existent these days (an example being the old UV EPROM) and programs are stored and run on one chip, with separate external memory being referred to (referenced/poled) by the device for settings and additional software/programs/firmware...


SCADA= Supervisory Control And Data Acquisition (this gets referred to a lot these days) and is basically a combination of sensors, relays, motor drivers and PLC's with an interface Board all connected to a computer , whether it be a Linux terminal, a Desktop PC or a Server in a remote location... this provides real time information and readings as well as control by the software and the User via the computer...mostly over a network..an example being in a factory etc...



ASIC= Application Specific Integrated Circuit, this is a specialist custom made microchip incorporating control, digital and analogue signal processing and other items such as amplification stages and high frequency Electronics, an example being an IC designed for a Mobile phone with memory for software which runs a screen driver, processes the signals from the microphone and out to the earpiece amplifier, poles the keypad or samples the touchscreen interface chip, etc....or an MP3 player operating from one chip with processing and audio output etc...

Firmware= operating software built into an Electronic device or Appliance/white goods to operate them, for example your printer has internal software which is classed as firmware, this is the name for pre-installed software required for normal operation of equipment...when talking about for an example a Fire Alarm System, Firmware or a Firmware Update may be mentioned (firmware basically translates as Fixed Software)








the common Programming Language used now is C/C++


There are many many Prototyping (Experimental) programming boards about these days with the software development kit (programming package) bundled and they can be bought from Maplins and Ebay, the more professional/Industrial ones can be bought from RS Electronics…

 

[grantr37]

NON-Volatile memory is set until it gets re-written (or damaged/corrupted) almost all modern memory is Non-Volatile..

Volatile memory requires a memory holding power source to hold the memory locations that are on/1 at High, this can be a permanent power supply, a small memory retention capacitor (only holds for a matter of hours or sometimes days) or a battery that can last for years...

 

[Knobhead]

I worked on the predecessors of PLC’s, first a Feranti Argus 1000 and then hard wired logic, Solicon, Norbit and Logicon 1 & 2. Compared to hard wired logic, PLC’s are slow.