01
Operation specification
What the equipment does, and in what order, set out in words and tables.
LADDER
OUR SERVICE
Machine builders, control panel makers and factory maintenance teams keep coming to us with the same shortage of ladder engineers. CodeCraft takes on both contract ladder development and the analysis and documentation of ladder programs that have become a black box. We take on work from anywhere in Japan, and one-off jobs are welcome.
Contract ladder developmentWe come to the site
Meetings
Design, development and simulation
Checks on the real machine and commissioning
Questions and fixes after handover(remotely where possible)
Ladder analysis and documentationOne visit, then remote
First visit: see the equipment and read out the program
Analysis and documentation
Meetings and delivery
* The only travel and accommodation costs in the quotation are for the first visit.
Prefer email? info@cocra.co.jp We reply within three business days.
LADDER DEVELOPMENT
Above: the development environment (Mitsubishi Electric MELSOFT GX Works3). Below: an operating screen we built for a touch panel. Client programs and screens cannot be published, so both are samples.
USE CASES
Too many jobs at once, and the in-house ladder engineer cannot get to all of them.
What we doWe take the overflow as a one-off job. Send the specification and we carry it through design and implementation.
The person who wrote ladder has left, and now the machine cannot be modified.
What we doWe start by analysing the existing program, and once we understand it we carry on into the modification or the new feature.
We would rather hand over the touch panel screens as well and have it all done together.
What we doWe design the ladder and the HMI screens together, propose a screen layout built around how it will be used, and can write the operating manual too.
LADDER ANALYSIS
Is there anyone who can explain what the control program on that machine actually does? Where years of modification have turned a PLC program into a black box, we decode it and turn it into material that anyone can read. We use AI to make the analysis faster, which keeps both the timescale and the cost down. Analysis and documentation on their own are very welcome as a job.
We have done this on a machine with almost no surviving design documents, reconstructing the control from how the equipment behaved and from what the people who had run it for years remembered, and writing it out as ladder. It was not a job of reading a specification; it was picking up one movement at a time. That ability to reconstruct behaviour is the same skill we use for analysis and for modification, and it sits at the centre of what we do. There is more detail under case studies.
The company that built the equipment has closed, and nobody understands what is inside the panel.
Solved by analysisWe read the program out of the PLC and decode the behaviour step by step, until what the equipment does today can be stated precisely.
No specification, no comments — every breakdown starts with an investigation, so recovery drags.
Solved by analysisWe produce the operation specification, I/O map and flowchart, so that when something stops, where to look is immediately obvious.
After years of changes, nobody can describe exactly what the machine currently does.
Solved by analysisThe findings go back in as a commented ladder program. Knowledge that depended on one experienced person becomes something the company owns.
DELIVERABLES
01
What the equipment does, and in what order, set out in words and tables.
02
Every input and output against the actual device, terminal and wire number.
03
The sequence drawn out, so maintenance staff can follow it.
04
Every rung and device explained, so the program itself can be read.
05
Ageing risk set out, with a recommended next step such as parts availability and the timing of a PLC replacement.
The images are sample deliverables we produced for a demo machine, not a real client job. Documents are written in Japanese as standard.
Mitsubishi Electric PLCs (GX Works3, FX5U and similar) primarily. Ask us about other makers.
CASE STUDIES
CASE
* The client name and specification details are withheld for confidentiality.
WHY CHOOSE US
AI-POWERED
An engineer always makes the final judgement and does the verification. On top of that, AI assists with the groundwork of analysis and documentation, so work that would take a long time by hand gets done faster — which keeps the timescale and the cost down.
READABLE DOCS
Software development taught us to write things so they can be read and maintained. What we produce is meant for your maintenance staff, not only for specialists.
REMOTE BY DEFAULT
For contract development we come to the site and see it through to commissioning. Analysis and documentation continue remotely after the first visit, which keeps the cost down even for equipment far from Miyakonojo.
CONFIDENTIAL
We work under an NDA. Programs and drawings are handled strictly, and where we mention work publicly the client name and specification detail stay out of it.
ENGINEER
CodeCraft is a small company. Ladder work, unlike system development, calls for hardware knowledge, so it is handled by the director, Matsumoto, himself. The person you first talk to is the engineer who designs and writes the program. The same person stays with the job from the first conversation through design, implementation and after-delivery support, so nothing gets lost between sales and engineering.
System development is a strength of ours as well, so we can also help build systems that collect data from PLCs and other equipment and make it visible.
Engineers are getting harder to find, and that is exactly why we want to be useful. Please feel free to get in touch.
Kenji Matsumoto, Representative Director
PROCESS
Consultation
We talk through the behaviour you need, online or on a visit, and you gather whatever exists — specification, timing charts, drawings. It is fine to come to us before the specification is settled. This first stage costs nothing.
Estimate
From what you have sent, we define the scope of work and present a delivery date and a quotation. We start only once you are satisfied with both.
Development & Delivery
We write the ladder and verify it in simulation, then come to the site to check it on the real machine and see it through commissioning. After handover, questions and fixes are handled remotely, and in an emergency we respond immediately — charged as travel and accommodation costs plus spot work at the hourly rate, or travel and accommodation costs only under a maintenance contract. Later additions are welcome too.
* Analysis and documentation jobs involve one visit at the start; the rest continues remotely.
PRICING
Approximate figures by type of job, to help with internal budgeting.
| Type of job | Guide | Notes |
|---|---|---|
| Small modification or added function on an existing ladder | From ¥50,000 | Clear specification, a few days of work |
| New ladder development for a machine | From ¥500,000 | Varies with I/O count and number of steps |
| Ladder analysis and documentation | From ¥150,000 | Operating specification, I/O map and flowcharts |
| Replacing an obsolete PLC with a current model | From ¥400,000 | Migration, verification and on-site commissioning |
| Spot work at an hourly rate | ¥8,000 per hour | Extra hands in a busy period, for example |
FAQ
Can we outsource just the ladder programming?
Yes. Ladder development on its own is a normal request for us. Send the specification and timing charts and we will design and implement from those. One-off jobs are welcome.
Can you modify or extend our existing ladder program?
We can. We follow the conventions of the existing program when adding to it, so that your own engineers can read the result without it feeling foreign. If nobody is sure what the existing ladder does, we can start from analysis.
The company that built our equipment has closed and nobody knows what is in the panel. Can you do analysis only?
Yes, and analysis-only work is very welcome. We read the program out of the PLC and decode the behaviour one step at a time, until what the equipment is actually doing today can be stated precisely.
What do we receive from an analysis job?
An operation specification, an I/O map and wiring correspondence table, a process flowchart, and a commented ladder program. We can also add a written assessment of ageing risk with recommendations for what to do next.
We are not nearby. Can you still take the job?
Yes. For contract development we come to the site for meetings, checks on the real machine and commissioning. After handover, questions and fixes are handled remotely, and in an emergency we respond immediately — charged as travel and accommodation costs plus spot work at the hourly rate, or travel and accommodation costs only under a maintenance contract. For analysis and documentation we visit once to see the equipment and read out the program; after that the work continues remotely, so the only travel and accommodation costs are for that first visit. Visits outside Japan need to be discussed in advance.
Which PLC makers do you work with?
Mitsubishi Electric PLCs primarily, including GX Works3 and the FX5U family. Ask us about other makers — we will tell you honestly whether it is within our range.
Can you work on a machine with no surviving drawings or documentation?
Yes. With older machines, no surviving documentation is the normal case rather than the exception. We reconstruct what happens, and in what order, from the machine itself and from the memory of the people who have run it for years. That reconstruction is the most important stage of the whole job — done carefully it removes most of the rework later. We will not turn a job down because the paperwork is missing.
Can you also replace an obsolete PLC with a current model?
Yes, where the replacement is PLC to PLC. Instructions and communication settings that conversion tools cannot carry over are rewritten by hand, and we verify the result in simulation before handing it over. We take the program migration, verification and commissioning support; panel and wiring work is normally shared with your local contractor.
How much does it cost?
Guide figures by type of job are set out under pricing. We give a formal quotation once we have your materials, and quotations are free of charge.
We are uneasy about handing over our program. Will it stay confidential?
We work under an NDA. Programs and drawings you entrust to us are handled strictly, and where we mention work publicly we withhold the client name and any specification detail.
Related: IoT development and factory monitoring／custom system development／AI development
CONTACT
Free. We reply by the next business day (Japan time).