The short answer
Choose the connection method from the equipment manufacturer’s termination design, the conductor type and size, environmental exposure, serviceability and the specified tools. Use a crimp only with the matched terminal, wire, tooling and acceptance criteria; use a terminal block only within its conductor, ferrule, strip-length and current/temperature data; solder only where the joint is designed for soldering and mechanically supported. Do not use solder as a generic repair for damaged flexible cable.
1. Start with the termination the equipment accepts
Inspect the power supply, controller, module lead, PCB and enclosure before choosing a method. A pluggable crimp housing, push-in terminal, screw clamp and solder pad are not interchangeable merely because the same copper conductor can be made to touch each one.
Record the exact part numbers and obtain the product drawing, application specification and installation instructions. Check conductor construction and cross-section, current, voltage, temperature, moisture, vibration, strain relief, inspection access and whether the joint must be disconnected for service.
2. Use a crimp as a controlled terminal system
TE Connectivity’s crimping guide identifies four elements of a good connection: correct tooling for the terminal and wire, the correct terminal for the application, properly prepared wire and a trained operator. Colour alone is not enough to prove a match.
Follow the exact strip length, conductor insertion, die or applicator, crimp location and inspection dimensions in the application specification. Do not substitute a generic hand tool when the specified terminal requires a controlled cavity or applicator. For production, retain setup evidence and first-off samples under the quality plan.
A pull check can be useful only when its method and acceptance value come from the relevant specification. Visual appearance by itself cannot prove electrical or mechanical performance.
3. Treat terminal blocks and ferrules as model-specific
A terminal block can be easy to inspect and service, but only within its own connection data. One Phoenix Contact PCB terminal example publishes different ranges for flexible conductors with and without insulated ferrules, a defined 10 mm strip length and a named crimp tool. Those figures illustrate why a generic “fits 1.5 mm²” rule is incomplete; use the actual model’s data.
Follow the terminal manufacturer’s statement on ferrules. WAGO’s ferrule guidance notes that connection technology and application determine whether a ferrule is needed or permitted. Do not tin fine-stranded conductors as a substitute for a ferrule unless the terminal manufacturer explicitly allows that preparation.
Where a terminal specifies torque, use the exact value, tool and maintenance instructions. Spring or push-in designs have different procedures and must not be assigned a made-up torque.
4. Solder only where the joint was designed for it
Solder is appropriate for designed PCB pads and other terminations whose manufacturer provides a soldering process. Control conductor preparation, temperature, dwell, wetting, polarity, cleanliness, insulation spacing and strain relief under that process.
Solder can wick into flexible strands and move the flex point beyond the joint. Support the cable so vibration or handling is not transferred to the rigid section. Heat-shrink may insulate a finished joint, but it does not correct poor wetting, an unsupported cable or an unapproved repair.
HSE guidance warns against unsuitable connectors and taped repairs to damaged cable. Replace damaged cable or use an approved repair method completed by a competent person; do not improvise an inline solder splice because it is convenient.
5. Compare the methods against the real job
Use this as a routing table, then confirm the exact product instructions. It is not a blanket ranking.
| Method | Good fit when | Evidence to require | Common reason to reject |
|---|---|---|---|
| Crimp terminal | Equipment uses a defined terminal/housing and repeatable production is needed | Matched terminal, wire, tool, strip length, crimp dimensions and inspection plan | Unknown terminal/tool combination or no acceptance specification |
| Terminal block | The equipment provides a rated clamp and service access matters | Exact model, conductor/ferrule range, strip length, current/temperature data and enclosure method | Conductor preparation or environment falls outside the model data |
| Soldered joint | A PCB pad or termination is specifically designed for soldering | Soldering process, pad/wire data, inspection criteria, insulation and strain relief | Generic cable splice, unsupported flex point or heat-sensitive surroundings |
6. Worked selection: a replaceable sign panel lead
Suppose a sign panel has a flexible 0.75 mm² lead, a documented plug housing for field replacement and a dry accessible enclosure. The housing drawing names a specific crimp contact, the contact application specification accepts that conductor, and the installer has the specified ratchet tool and inspection dimensions. The crimped contact is the defensible route because it preserves the designed detachable interface.
If the tool or exact contact is unavailable, soldering the wire to the loose contact is not an equivalent shortcut. Record the design gap and obtain the correct system, or use a different connection only after the equipment designer approves a documented alternative. If a terminal block is selected instead, reassess enclosure space, touch protection, conductor range, ferrule policy, current, temperature and strain relief.
7. Commission with a repeatable quality record
TE’s connector troubleshooting guide recommends a clear, data-based problem statement: define the as-is and desired states, where and when the issue occurred, how it was detected, quantities affected and impact. It also recommends product drawings and specifications, annotated photographs, labels and retained samples.
For each connection process, record part and batch numbers, cable construction, preparation length, tool identification and calibration status where applicable, operator, first-off result, inspection measurements, defect quantity and retained sample. Keep photos of both accepted and rejected examples using the same metric.
Commission the completed branch under the competent person’s approved electrical and functional test plan. Glowfy does not currently list a general connector range, so send the termination schedule for guidance without assuming stock or a universal connection recommendation.
Frequently asked questions
Is crimping always better than soldering for LED wiring?
No. A crimp is strong and repeatable only as a matched terminal, wire and tooling system. Solder is appropriate where the termination is designed and supported for it. Follow the exact equipment design.
Should stranded cable always have a ferrule before a terminal block?
Not always. The terminal manufacturer’s data must say whether a ferrule is required or permitted and which ferrule style, size, length and tool apply.
Can I tin stranded wire before putting it in a screw terminal?
Do not assume so. Tinned strands can behave differently under clamping pressure. Use the conductor preparation stated for the exact terminal, and use a specified ferrule where applicable.
What should a connection quality record contain?
Record exact parts and cable, preparation, tool, operator, inspection dimensions or criteria, quantity checked, defects, photographs and a retained sample where the quality plan requires one.
Technical references
Use the current datasheet for the exact product you install. These manufacturer and standards resources explain the general principles.
Review the termination schedule before production
Send the equipment terminals, cable construction, environment and proposed tools so Glowfy can help structure the compatibility checks without assuming a generic connector.