WIRE-TERMINATION TECHNOLOGY GUIDE
Screw vs spring terminal blocks.
Compare how each connection is operated and controlled—then verify the conductor, PCB footprint, exact ratings, drawing and physical sample.
Termination method is one decision axis. PCB architecture is another.
COMPARE THE CONDUCTOR INTERFACE
Neither technology is a universal winner.
Screw and spring describe how the conductor is retained. They do not by themselves decide whether a product is fixed to the PCB or pluggable, nor do they establish its rating, footprint, conductor range or field performance.
SIDE-BY-SIDE COMPARISON
Compare the process that must work on the real PCB.
A screw-operated pressure element clamps the conductor. The exact mechanism can use a pressure plate, wire guard or another model-specific design.
A spring element applies the conductor contact force. Spring-cage, push-button, lever and direct Push-in operation are distinct designs.
Prepare and insert the conductor, then tighten using the exact product's specified tool and torque procedure.
Open the spring with the specified actuator or tool, or insert directly only where the exact product supports direct Push-in.
Allow room for the screwdriver, screw head, conductor entry and any inspection or service operation.
Allow room for the push-button, lever or actuation shaft, conductor entry and the correct release motion.
Verify solid, stranded or ferruled conductor acceptance, strip length, wire range and any preparation rule for the exact model.
Verify the same conductor details; spring technology alone does not prove that every conductor type can be inserted in the same way.
Control conductor insertion, stripping and tightening torque. Do not copy a torque value from a similar housing.
Control stripping, full insertion and actuator state. Direct-insertion designs may remove a tightening step, but only when documented.
Release and re-tighten with the specified tool and procedure while preserving access to the installed terminal.
Release through the product's defined button, lever or actuation shaft; do not pry the contact through the wire opening.
Pitch, pin layout, housing envelope and mounting direction remain properties of the exact terminal, not of screw technology in general.
The same rule applies. A spring model with the same nominal pitch is not automatically footprint-compatible with a screw model.
Confirm current, voltage, conductor range, temperature, materials, documents, drawing and a production-intent sample.
Confirm the same evidence. No universal current, voltage, vibration or service-life advantage is claimed at family level.
EIGHT-QUESTION DECISION ROUTE
Choose from wiring, access and verification constraints.
- 01
How many terminations will be made in production or field wiring?
Map the real wiring sequence for each candidate. A shorter sequence matters only when the exact conductor and model support it.
- 02
Which conductor types and preparations must be accepted?
List solid, stranded and ferruled conductors separately, with cross-section, strip length and ferrule requirements.
- 03
Can the assembly process control the required screw torque?
If using screw termination, define the correct driver, access, torque value and verification method for the exact model.
- 04
Is the spring terminal direct Push-in, button, lever or tool-actuated?
Do not use the word spring as the operating instruction. Confirm the actual actuation and release method.
- 05
What access remains after the PCB enters its enclosure?
Check conductor approach, bend space, screwdriver or actuator movement and future service access in the installed assembly.
- 06
Are vibration, temperature or maintenance conditions demanding?
Require product-level test evidence and the intended installation condition; do not transfer a family or competitor claim.
- 07
Is the PCB footprint or enclosure opening already fixed?
Treat the drawing, holes, pin layout, terminal height and wire-entry direction as hard constraints before changing technology.
- 08
Are all ratings and required documents confirmed?
Close current, voltage, conductor range, temperature, materials and market documentation before sample approval.
CURRENT YIHENTRA REFERENCES
Move from connection method to exact model evidence.
The current catalog lists 14 PCB screw models and 11 spring-terminal references. The selected models below span the current pitch range; they are not claimed as direct substitutes.
PCB screw references
Six documented examples. Confirm the exact rating, conductor, torque, footprint and ordered configuration.
- KF128L-3.81Low-profile PCB screw terminal block3.81mm · Vertical PCB mount
- KF103-5.0PCB screw terminal block5.0mm · Vertical PCB mount
- KF128H-5.08High-profile PCB screw terminal block5.08mm · Vertical PCB mount
- KF635PCB screw terminal block6.35mm · Vertical PCB mount
- KF129-7.62PCB screw terminal block7.62mm · Vertical PCB mount
- KFA(B)-1016A/B type high-current PCB screw terminal block10.16mm · Vertical PCB mount
Spring references
Six drawing-linked examples. Electrical ratings and final configurations remain pending supplier confirmation.
- KF15EDGKD-2.5Spring terminal block2.5 mm · ratings pending
- KF141R-2.54Spring terminal block2.54 mm · ratings pending
- KF2EDGKN-3.5Spring terminal block3.5 mm · ratings pending
- KF2EDGKD-5.08Spring terminal block5.08 mm · ratings pending
- KF142V-5.08Spring terminal block5.08 mm · ratings pending
- KF142V-7.62Spring terminal block7.62 mm · ratings pending
TECHNICAL BASIS
General principles checked against manufacturer references.
These sources define generic connection mechanisms only. Their product claims and ratings are not transferred to YIHENTRA models.
- 01
Phoenix Contact: Screw connection technology ↗
Explains screw-operated tension-sleeve, wire-guard and front-screw conductor clamping principles.
- 02
Phoenix Contact: Spring connection technology ↗
Explains tool-actuated spring-cage operation and the defined spring contact force.
- 03
Weidmüller: PCB wire-connection technologies ↗
Separates PUSH IN spring, SNAP IN and clamping-yoke screw connection methods for PCB products.
- 04
WAGO: PCB terminal blocks and connectors ↗
Shows multiple spring-pressure and direct-insertion variants used in PCB connection products.
EVIDENCE FOR A USEFUL RFQ
Send the wiring process and board constraints.
Include conductor preparation, tool or actuator access, pitch, positions, PCB footprint, current, voltage, environment, quantity, target market and required documents.
BUYER FAQ
Screw and spring connection questions.
Is every spring terminal block a Push-in terminal block?
No. Push-in is a spring-based direct-connection method, but other spring terminals use a push-button, lever or tool-actuated spring cage. Confirm the exact operating method.
Which carries more current: screw or spring terminal blocks?
There is no universal family-level answer. Current and voltage depend on the exact contact system, pitch, conductor, thermal conditions, standard and approved product data.
Is a spring connection always tool-free and maintenance-free?
Do not assume so. Some spring designs support direct or lever-actuated tool-free wiring, while others require a tool to open the spring. Service claims must be supported by the exact product documentation.
Can a spring model replace a screw model with the same pitch?
Not from pitch alone. Compare pin layout, hole size, housing envelope, wire-entry direction, actuation access, ratings, conductor acceptance and a physical sample.
Do stranded wires need ferrules for both technologies?
The answer is model- and application-specific. Confirm whether bare stranded, ferruled or other prepared conductors are accepted and follow the stated strip length and preparation rules.
What should be included in a screw-versus-spring RFQ?
Send the application, existing model or PCB drawing, pitch, positions, conductor type and range, strip or ferrule requirement, current, voltage, mounting and wire-entry direction, tool-access limits, quantity, target market and required documents.