OEM PLC Training Tips :
On this page we will continue to post tips useful to the machine designer OEM. So best to bookmark and check back often.
"Tips plc controller training and ladder programming PLCs for the OEM Company and maintenance personnel." Some of these PLC training tips may be from a equipment manufacturer association, OEM PLC news, etc.. If you are asking what does a field service technician do, some of the field service technician training about PLCs here will offer insight.
PLC Programming tips:
Start with industry standard program structure. Provide a cross reference subroutine, a startup subroutine , keep main PLC program file clean with mostly just jump to subroutine rungs and critical safety rungs. (Have a structure in the first place.)
Use common PLC programming conventions like plugging timers in forward / reversing motor logic. Use variable (memory location) instead of constant for all source and destination fields. Only use real world I/O addresses in cross-reference subroutine. Provide 20% additional resources (memory allocation, etc.) in case online programming is required.
Use common industry naming conventions like AFI (Always False Input), and XREF (Cross Reference). Keep symbols/tags as short as possible, element descriptions as detailed as possible.
Great advice on which PLC programming language to use in which application can be found in Control Design magazine article "Learning IEC 61131-3 programming language"
Control Panel Design tips:
* Have an outside-the-panel PLC communication port and fused 120-V outlet.
* If it's an ac-powered PLC, have the line filter on 120‑V control power come off the transformer's secondaries.
* Bring critical warning lights, such as PLC fault, battery, force, comm, outside the panel or to the HMI.
* Use aux contacts on E-stops and disconnects to detect them in the PLC and/or HMI.
* Consider providing PLC program backup on a PLC EEPROM in a PLC that reloads the program automatically on memory fault.
Tips on working with automation control:
Ensure that service techs and start-up techs clearly document changes, and share that documentation with maintenance.Anything to do with FORCES is a safety issue! Installing, removing, enabling and disabling should only be done with extreme hesitation and caution, Research of the address to be forced should first be double checked. Never leave a force at customer's site.
Have an instructional document control rung comment on first rung visible in every PLC program. Encourage your customers to manage and back up regularly all the PLC programs in their facility. If placing your machine on the customer's industrial network, do not use any IP channel that is device's default number. Recommend that your customers have at least one person per shift who has received the foundational PLC training.
OEM Machine Design Standards:
The machine design standard should be start with the industry standards and improve from there. This will help insure you are always ahead of the competition.
- Use the new NFPA 79 2016 edition, with its European counterpart Standard IEC 60204-1..
- Follow Chapter 5 - The OSHA's Chapter 5: Utilization of Industry Consensus Standards 29 CFR 1910.212 .
- Folow ISA/PLCopen backed IEC 61131-3:2013 programming languages standards by International Electrotechnical Commission (IEC).
- Refer to ISO Standards - ICS 21.020: Characteristics and design of machines, apparatus, equipment.
- Use industry PLC programming conventions so they are more familiar and understood by customer.
- Use standard industry naming conventions for the same reasons as above. .
More external Machine Design tips:
As you may have already picked up, Control Design Magazine is one of our favorite resource. There you can get the latest and greatest on new technology like the evolution from PLC/DCS to PAC free eBook. You should also join the professional industrial group of BIN on LinkedIn. (12k+ strong professional members) After all the whole purpose of networking is the more relevant minds get together the more new ideas and insight each can gain. You get a whole more out of networking with 12,000, than you will with networking with on 2 people. We recommend LinkedIn over places like PLCtalk or MrPLC because when you are getting recommendations and advice, better to get from someone you can view their whole professional profile on LinkedIn, than on one of the other aforementioned where the person on the other end is anonymous and you not knowing anything about who the advice is coming from.
Who better to know the equipment you are using in your design than the people who made it. That said, never forget their biases, their recommendations may have the 'sell' as priority over what is actually best for your particular solution. Also they are not professional trainers, so for those new to technology, we recommend BIN PLC Training over vendor PLC training. But when it comes to intermediate to advanced training, we recommend you seek the PLC vendor for that particular project.
More Machine Design resources ...
This is advice for both the OEM designing the control panel, and to give to their end-users (plant maintenance, who has to maintain and work with that control panel, long after start-up is complete.)
Least expensive solutions, to most ...
* Put power line filters on 120v control side before PLC power.
* Make backups of every PLC program, every 6 months whether you need to or not.
* Replace PLC battery every 3 years whether you need to or not.
* Rout 120v and PLC programming port to outside the panel
* Network all your plant PLCs to the engineering/maintenance office for easier backup and access without LOTO
* Have panels designed with DC PLC in external sub-panel
REF: BIN95 Blog Control Panel Design Guide
REF: Article: Maintenance Management of plant PLCs