PLC Processor, Power Supply & I/O Repair
Failed PLC power supplies, processors, and I/O — including obsolete families that are no longer sold new. ControlLogix, CompactLogix, SLC 500, PLC-5, MicroLogix, SIMATIC S7 and more.
PLC repairs get a free bench evaluation. Obsolete families (SLC 500, PLC-5, S5) are a specialty — repair keeps a working spare alive when replacements no longer exist.
✓Fixed — or it's free
Unrepairable units are refunded; evaluations cost $0
✓24-month warranty
Every repair covered, parts and labor
✓3–5 business days bench time
Rush (1–2 day) and emergency service available
✓Program preserved
Your application and settings stay in the unit
PLC Modules repair services
What this category covers
- ▸Allen-Bradley ControlLogix / CompactLogix
- ▸Allen-Bradley SLC 500 & PLC-5 (obsolete)
- ▸Allen-Bradley MicroLogix
- ▸Siemens SIMATIC S7-300 / S7-400
- ▸PLC rack power supplies
- ▸Analog, digital & communication modules
Failures we see every week
- ▸Rack power supply failure (dead rack)
- ▸Processor fault LEDs / dead CPU
- ▸Failed I/O channels
- ▸Battery-loss program corruption
- ▸Communication port / module failure
- ▸Capacitor aging on obsolete supplies
Part numbers in this category
Frequently asked questions
Can you repair my dead PLC CPU?
Usually no — and we say so up front. CPU failures are dominated by proprietary silicon with no component-level repair path. But the fault is very often the rack power supply, not the CPU: we repair those flat-price, test-and-verify CPUs honestly, and repair the I/O and comm modules around them.
The module is obsolete — is repair realistic?
Obsolete I/O and comm modules are where repair shines: failures live in generic components (drivers, optocouplers, relays, capacitors) that remain available long after the module itself doesn't.
Machine down? Let's get it back up.
Start a repair online in two minutes, or send us the part number for a free technician review.
The Fixed-or-Free Guarantee: if we can't repair it, you don't pay for the repair.
Call (817) 799-7332 · 📱 Text us a photo of your unit · Email repairs@controlboardlab.com