Siemens PLC programming in Kenya: S7-1200, S7-1500, S7-300 and LOGO!

Siemens SIMATIC PLCs control a large share of the factories, mills and water plants in East Africa. We write, modify and troubleshoot Siemens PLC programs in ladder (LAD), function block diagram (FBD) and structured control language (SCL), and we migrate ageing S7-300 and S7-400 systems to S7-1500 in TIA Portal.

Siemens PLCs we work on

• SIMATIC S7-1500: for production lines and process plants, with PROFINET I/O and drives
• SIMATIC S7-1200: for single machines, pumping stations and skids
• S7-300 and S7-400: legacy systems we maintain and migrate to S7-1500
• LOGO!: logic modules for small controls, lighting and pumps
• ET 200SP / ET 200MP: distributed I/O

Software: TIA Portal (STEP 7 Basic and Professional), STEP 7 Classic V5.x, LOGO! Soft Comfort. Networks: PROFINET, PROFIBUS DP, Modbus TCP and RTU, OPC UA.

Siemens PLC services

• New S7-1200 and S7-1500 programs for machines, conveyors and process lines
• Online diagnosis of CPU stops, diagnostic buffer events and PROFINET device faults
• S7-300/S7-400 to S7-1500 migration, including STEP 7 Classic to TIA Portal conversion
• Adding OPC UA or Modbus TCP so SCADA and dashboards can read production data
• Recovering and documenting programs on machines with no backup

Signs your PLC system needs attention

• The machine stops with faults nobody can explain, or the only person who understood the program has left
• There is no current backup of the program, or the backup does not match what is running
• Spare CPUs and I/O cards are discontinued, expensive or months away
• Operators work around the sequence by hand because the logic no longer matches the process
• You want production data, remote access or new functions that the old program cannot provide

How we approach a PLC job

1. Upload and back up the running program and hardware configuration before any change.
2. Document the I/O and the sequence with your operators, so everyone agrees what the machine must do.
3. Write or modify the logic offline, structured and commented, and test it with simulation where possible.
4. Commission on site: test every input, output, interlock and alarm, then run under real production load.
5. Hand over the final program, I/O list and drawings, and train your technicians on fault finding.

Tips from our engineers

Migrate S7-300 before it fails

Siemens is phasing out S7-300 and S7-400 hardware. A planned migration to S7-1500 during a shutdown costs far less than an emergency rebuild when a CPU fails and no spare can be found.

Use know-how protection carefully

Protected blocks keep your program safe, but lost passwords lock you out of your own machine. Store passwords with the project archive, not on a sticky note in the panel.

Related guides

See also Siemens PLC, HMI and drive services overview, Siemens HMI programming, Siemens VFD programming and commissioning, our PLC service page.