Engineering Selection Reference
Double-sided FR4 PCB: relay-board fabrication and RFQ requirements
Double-sided FR4 relay-board fabrication requires review against current drawings. For double-sided FR4 relay control board fabrication, provide load copper paths, terminal leads, and isolation slots. Finished copper of 70µm is a reference target; fine traces and safety distances cannot be reused directly. Deliver finished-hole, hole-wall copper, and electrical-test records; verify temperature rise only under agreed load and cooling conditions.
For double-sided FR4 PCBs, first define bare-board prototyping or production scope. Please provide Gerber data, drill files, board outline, and layer stackup, materials/processes, quantity, and manufacturing acceptance requirements. Double-sided 2oz reference finished copper serves load circuits; signal density is low, while insulation layout matters
Why choose this structure for relay control boards
When loads mainly involve relays, terminals, and low-speed I/O, double-sided FR4 can clearly separate main-current paths from control traces. The 70µm reference finished copper is a starting point for load paths. Procurement focuses on copper cross-sections, holes, and insulation boundaries; low-speed controls need not be forced into multilayer high-speed stackups.
How much does double-sided FR4 relay-board fabrication cost?
Prices comprise double-sided material, 70µm reference finished copper, component insertion holes and NPTH isolation slots, lead-free HASL, and electrical tests. Compared with ordinary 35µm small-signal double-sided boards, added copper weight, hole specifications, and large pads change etching and assembly conditions. Align outline, slot length, load nets, and quantity when comparing prices; define loaded temperature-rise verification separately.
Quotation terms depend on the approved files, quantity, material supply, tests and delivery requirements.
Prepare a structured RFQ or use the short inquiry form.
Enter the following items in one itemized quotation: specify cost units and tax/shipping basis, with separate columns for first orders and same-revision repeat orders. The table is a procurement breakdown method, not a ready-made price list; reference specifications require approval against current fabrication drawings.
| Quotation items and pricing boundaries | Configuration inputs to confirm | Repeat orders and revision changes |
|---|---|---|
| Materials/fabrication, quoted per batch or accepted board | Shengyi S1000-2M FR4 reference grade; confirm current material documentation; 2 layers; base copper 35µm/finished reference target 70µm | Recurs on repeat orders; material, layer-order, or copper-weight changes require requotation |
| Holes and forming, per approved hole table | Ø0.40mm through holes; relay lead holes per component drawings; NPTH isolation slots | Reorders follow the same revision; review operations before relay-load-boundary changes |
| Surface finish/packaging, noting areas and batches | Lead-free HASL; large-pad/through-hole soldering areas | Incurred by actual batch; confirm packaging, storage conditions, and surface-finish substitutions separately |
| Engineering/tooling preparation, identifying one-time or per-batch charges | Relay-load boundaries: provide load type, contact nets, and insulation-clearance drawings to decide on slots or local copper keepouts. | Verify file revisions, ownership, and storage condition before reusing old tooling; do not assume reuse is free |
| Structural/special inspections, identifying coupons, hole groups, or samples | Agree critical-clearance and slot-dimensional reports; bare boards do not replace loaded relay-life verification. Record finished-hole/slot tolerances and freeze hole tables after confirming insertion fit. | List initial prototype validation and per-batch sampling separately; quote per-board requirements separately rather than assuming everything is completed once |
| Delivery scope, reports, and accepted quantity | Double-sided bare PCB, copper-weight/hole-diameter fabrication drawings, isolation-slot dimensions, electrical-test records, and project-agreed temperature-rise verification data. | Retain revision links and batch records on repeat orders; list component assembly, firmware, and complete-unit testing separately |
Should relay control boards use double-sided or four-layer construction?
Double-sided construction is more direct when low-speed I/O and terminal-load layouts have enough space. Compare four-layer reference-ground structures when load returns cross sensitive controls or analog inputs are dense. Four layers cannot replace load copper cross-sections and safety isolation; lower double-sided costs do not justify compressed spacing.
| Comparison Dimension | Double-sided FR4 printed circuit board fabrication | Four-layer FR4 PCB Prototyping |
|---|---|---|
| Material and Grade | Shengyi S1000-2M FR4 reference grade; confirm current material documentation | Isola 370HR FR4 |
| Layer Count and Structure | 2 Layer | 4 Layer |
| Hole Structure and Dimensions | Ø0.40mm through holes; relay lead holes per component drawings; NPTH isolation slots | Ø0.30mm through holes; high-impedance input guard rings remain uninterrupted by through holes |
| Application | Relay I/O modules; appliance control interfaces | Bridge-sensor acquisition; precision ADC front ends |
How much current can a 2OZ relay board carry?
2OZ alone cannot determine current capacity. Combine terminals, pads, narrow traces, and via barrels into the complete load path, assess voltage drop from length and cross-section, then measure temperature rise under specified energization time, ambient, and cooling conditions. The 0.25mm reference spacing is manufacturing geometry, not a high-voltage safety clearance.
| Decision Sequence | Required project inputs | Agreed records and deliverables |
|---|---|---|
| 1. Define application and scope | Provide load type, contact nets, and insulation-clearance drawings to decide on slots or local copper keepouts. | Agree critical-clearance and slot-dimensional reports; bare boards do not replace loaded relay-life verification. |
| 2. Confirm structural requirements | Provide actual relay and terminal lead dimensions, distinguishing finished-hole diameters from drill-tool sizes. | Record finished-hole/slot tolerances and freeze hole tables after confirming insertion fit. |
| 3. Align nets with fabrication targets | No impedance acceptance for low-speed relay control; design creepage/electrical clearance separately | Provide target nets, layer pairs, and verification scope; review with Ø0.40mm through holes, relay lead holes per component drawings, and NPTH isolation slots |
| 4. Confirm quotation and release revision | Shengyi S1000-2M FR4 reference grade; confirm current material documentation; 1.60mm reference target; lead-free HASL; large-pad/through-hole soldering areas | Request quotations using material/pattern/inspection lists at the same revision; list unapproved substitutions as separate alternatives rather than including them in the baseline quotation |
Relay control board manufacturing specifications
| Specification Items | Reference configuration or target |
|---|---|
| Material and Grade | Shengyi S1000-2M FR4 reference grade; confirm current material documentation |
| Layer Count and Structure | 2 Layer |
| Total Board Thickness | 1.60mm reference target |
| Dielectric thickness and interlayer relationship | Single-core target approximately 1.50mm; determine thickness after subtracting copper/process allowances |
| Base Copper and Finished Copper | Base copper 35µm/finished reference target 70µm |
| Hole Structure and Dimensions | Ø0.40mm through holes; relay lead holes per component drawings; NPTH isolation slots |
| Trace Width and Spacing | 0.25/0.25mm reference design |
| Impedance Target and Measurement Methods | No impedance acceptance for low-speed relay control; design creepage/electrical clearance separately |
| Surface Finish | Lead-free HASL; large-pad/through-hole soldering areas |
| Application | Relay I/O modules; appliance control interfaces |
| Deliverables | Double-sided bare PCB, copper-weight/hole-diameter fabrication drawings, isolation-slot dimensions, electrical-test records, and project-agreed temperature-rise verification data. |
Tradeoffs between double-sided return-path space and heavy-copper clearances
Double-sided costs/inspection are more straightforward, but limited space can force load returns through control regions. Heavy-copper etching complicates fine traces; reference 0.25mm spacing is not a high-voltage creepage rule. Compare four-layer acquisition boards when more analog isolation or dense signals are needed.
Finished terminal holes, thermal pads, and NPTH slots: manufacturing checks
Define terminal/relay lead holes from maximum component leads and assembly allowances, not minimum via values alone. Separately inspect heavy-copper etch spacing, pad thermal connections, and isolation-slot burrs; V-scoring must avoid safety-clearance-sensitive areas.
Hole-wall copper, isolation, and condition-specific temperature rise: acceptance items
Electrical testing verifies connections and isolation; microsections check finished copper/hole-wall copper. Verify load-path temperature rise/voltage drop with specified loads, energization time, ambient, and cooling boundaries. Any current-capacity value must come from such condition-specific testing or calculation.
Relay control board delivery scope
Applications: relay I/O modules; appliance control interfaces.
Double-sided bare PCB, copper-weight/hole-diameter fabrication drawings, isolation-slot dimensions, electrical-test records, and project-agreed temperature-rise verification data.
Load nets, relay lead holes, and slots: quotation inputs
Submit load nets, relay lead holes, and slots, converting tabled targets into inspectable drawings. The following inputs separately define artwork, material, or structural inspection scope; freeze quotation revisions with approved drawings.
| Project inputs required for review | Engineering decisions | Records/delivery as agreed in the order |
|---|---|---|
| Relay Load Limits | Provide load type, contact nets, and insulation-clearance drawings to decide on slots or local copper keepouts. | Agree critical-clearance and slot-dimensional reports; bare boards do not replace loaded relay-life verification. |
| Large Pads and Through-Hole Pins | Provide actual relay and terminal lead dimensions, distinguishing finished-hole diameters from drill-tool sizes. | Record finished-hole/slot tolerances and freeze hole tables after confirming insertion fit. |
Double-sided FR4 PCB fabrication: pricing, selection, and procurement FAQ
How much does double-sided FR4 relay-board fabrication cost?
A project-specific quotation requires review of the available files, quantity, materials, requested tests, delivery destination, taxes, shipping, and trade terms. Add specified materials, processes, and inspections not yet included to the total cost. Standard board references do not cover every configuration of this product. No current unit prices are published here; request an itemized quotation for the approved scope.Review quotation inputs and scope.
Should relay control boards use double-sided or four-layer construction?
Choose double-sided construction first when low-speed I/O, terminals, and loads have enough space; compare four layers when sensitive controls and load returns are difficult to separate. More layers do not replace load copper cross-sections or insulation distances, and fewer layers cannot be achieved by shrinking safety clearances. Review the comparison
How much current can a 2OZ relay board carry?
2OZ alone gives no universal ampere rating; examine copper-path length, narrowest cross-section, vias, and contacts. Check the entire path against load, power wiring, ambient, and allowable temperature rise. Reference 0.25mm spacing is not a system safety clearance. Review the comparison
Can relay lead holes be fabricated using via dimensions?
No. Determine finished component insertion holes from maximum leads and assembly allowances; plating changes hole diameter. The reference 0.40mm through hole does not mean every relay lead hole uses that size.
Does a relay-board price include relays and terminals?
This scope is bare PCB fabrication; components, through-hole soldering, and loaded tests require separate PCB assembly quotation items. Compare bare-board and assembled delivery using the same schematic and BOM to avoid mixing pricing objects.
Do relay control boards always need ENIG?
For generous through-hole clearances and large pads, compare lead-free HASL first; consider ENIG for fine-pitch parts or specific material-preparation requirements. Finishes cannot replace hole-diameter, hole-wall copper, or loaded relay-life verification.
Can removing slots lower a relay control board quotation?
Load-isolation boundaries, materials, and fabrication drawings jointly determine whether slots are needed; do not remove them first to reduce price. Compare profiling costs for two approved layouts, one retaining slots and one rerouted, while confirming copper-to-slot distance, burrs, and actual insulation paths. Bare-board electrical tests cannot replace loaded safety verification.
How are per-board and per-panel double-sided FR4 quotations converted?
Check terminal/relay finished holes, NPTH isolation slots, and large pads against assembly before panelization; reference via sizes do not define every component hole. State deliverable boards per panel, purchased panels, and board/panel delivery condition. Divide actual panel fabrication charges by corresponding accepted board count; list setup, specialized inspections, and packaging separately, without promising yield from theoretical utilization.
How should first-order one-time charges and reorder costs be separated for double-sided FR4 fabrication?
First confirm relay-load boundaries, large-pad, and insertion-hole documentation, stating whether engineering, tooling, or test setup is charged once. Agree critical-clearance and slot reports; bare boards do not replace loaded relay-life verification. Verify files and ownership before tool reuse; current materials, fabrication, and approved inspections still incur costs. List renewed preparation after changes separately rather than relying on the old total.
Can I obtain a double-sided FR4 budget before relay-load-boundary documentation is complete?
Describe application, outline, quantity, and available drawings for a budget identifying gaps. Formal review needs load type, contact nets, and insulation-clearance drawings to decide slots and local copper keepouts. Deliver critical-clearance and slot reports; bare boards do not replace loaded relay-life verification. Confirm fabrication/inspection quotes after conditions freeze. Initial inquiries need not include every file, but estimates do not cover undefined structures by default.
What must be reconfirmed when materials, hole tables, or installation conditions change on a double-sided FR4 reorder?
Provide actual relay/terminal lead dimensions, distinguishing finished-hole diameters from drill sizes. Record finished-hole/slot tolerances and freeze hole tables after insertion-fit confirmation. Map changes to previous material/hole-table/mechanical files item by item to determine drawing, process, or measurement updates; unchanged product name and layer count do not establish identical reorder conditions.
If two double-sided FR4 quotes use the same material, which configurations still need comparison?
Distinguish 35µm base copper from the 70µm finished target, then check insertion holes/isolation slots and HASL areas. Loaded life or temperature rise requires separately defined verification; double-sided bare-board continuity cannot replace it.
Which reports should link to board identifiers before double-sided FR4 prototypes move to production?
Agree critical-clearance and slot reports; bare boards do not replace loaded relay-life verification. Record finished-hole/slot tolerances and freeze hole tables after insertion-fit confirmation. Link material lots, approved fabrication files, and results to current sample identifiers; production uses the revision with issues closed. Old coupon/artwork reports support comparison but cannot replace current inputs; define uncovered complete-system objects separately.
When small-batch double-sided FR4 unit prices fall, how can I tell whether total procurement costs decreased?
Compare equivalent-function double-sided and four-layer relay designs while retaining load holes/slots and insulation requirements, adding components, through-hole assembly, and loaded testing separately rather than looking only at fewer-layer board prices. Add setup, fabrication, agreed inspections, packaging, and shipping, then divide by accepted delivery quantity for equal-scope totals and per-board allocation. Use current quotes for amounts and rates; assume no fixed discount.
Comparison of relay control board with adjacent board types
Current configuration distinction: double-sided 2oz reference finished copper serves load circuits; signal density is low, while insulation layout matters
- Four-layer FR4 precision analog acquisition board — Continuous reference ground and guard-ring regions support weak signals, avoiding shared circuits with relay loads
- Six-Layer FR4 Power Digital Control Board — Six-layer dual-copper-weight FR4 combines power capacity and signal return paths in one stackup
FR4 PCB complete product catalog · All PCB Products
Material and design basis for relay control boards
- Engineering reference | Shengyi S1000-2M: grade, supply bases, and material documentation: grade-documentation entry point; unverified performance is not cited
- Engineering reference | Basic PCB design rules: copper weight, spacing, and hole diameter: General manufacturing design method
When citing these resources, record material revisions and design conditions for double-sided 70µm finished copper and insertion holes; first articles focus on hole-wall copper, isolation, and condition-specific temperature rise. After material, copper-weight, or hole-structure changes, update drawings and inspections before release.
Request Quote for This PCB Configuration: cite product ID 226, attach critical circuit/interface information and quantity, and list specifications to retain or adjust.
