LED Tube Type A, B and C Compatibility Reference
Compare ballast-compatible, ballast-bypass and external-driver LED tubes, then check exact lamp, ballast, luminaire and retrofit instructions before replacement.
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Compare supply arrangements
Type A, B and C distinguish how an LED tube receives power. T8 or T12 describes a size family rather than an electrical retrofit arrangement. A physically fitting tube does not establish ballast, lampholder or luminaire compatibility.
| Tube arrangement | Power path | Documentation to retain |
|---|---|---|
| Type A | Operates with a compatible fluorescent ballast. | Exact tube and ballast model pairing on the manufacturer compatibility list. |
| Type B | Operates from the specified line supply through the documented bypass arrangement. | Exact retrofit instructions, supply limits and required luminaire marking. |
| Type C | Operates from a specified external LED driver. | Approved lamp/driver combination and conversion instructions. |
| Hybrid A/B | Supports the specifically documented modes. | Instructions for the selected mode; the hybrid name is not universal compatibility. |
Check details below the type label
Type B products can differ in single-ended or double-ended power and lampholder requirements. Do not infer these details from tube length, pin shape or the word “bypass.” Type A compatibility is specific to the ballast and tube models; a fluorescent ballast label alone is not a match.
For a Type C conversion, verify output mode, permitted lamp count and approved wiring arrangement from the complete retrofit documentation. Driver watts alone cannot establish compatibility.
Create a replacement record
- Record luminaire identity, original ballast and existing lamp details.
- Identify the exact new tube/kit and the intended operating mode.
- Retain compatibility list, installation instructions and required labels.
- Resolve lampholder, environmental or control differences through the product documentation.
This is an identification reference, not a general rewiring tutorial. Read LED driver output for current/voltage regulation and lighting control interfaces for the separate dimming system. Record the final product combination on the job card.