Single-channel DC mechanical-relay study using a soldered Finder relay and functional host/coil isolation. The retained study is 80 × 89.5 mm; contact, coil, converter, fuse and thermal limits remain unqualified.
Baseline documentation snapshot: 2026-10-11, before the requested connector/protection/usability revision program. New revision features require their own reviewed source and qualification evidence.
This page documents an unqualified engineering study, not a released or tested product. Saved CAD, renders and automated checks do not establish a safe assembly, compatible cable, firmware support or a usable current rating.
The retained design record states:
The selected study is80×89.5mm with the original soldered Finder relay, functional host/coil isolation and mounting positions. R_IND1 now conditionally reuses Smoothieboard V1 record58:5.6kΩ10%0603, received lot rating≥0.1W. This supersedes the historical4.7kΩ0805 indicator below; at13.2V/Rmin5040Ω the conservative resistor-only bound is34.571mW. Host and coil trunk selections widen0.6→0.7mm while short local escapes remain. Arrays offer no demonstrated one-channel outline benefit; DRV8860 would change the command interface and firmware.
Board-specific qualification limits: Received lot rating, relay/contact thermal, isolation, fuse, converter and physical qualification remain open.
The exact connector orientation, pin mapping and supply ownership must be taken from the selected revision’s schematic and connection specification. Do not infer wiring from the connector shape.
Power off before connecting or changing jumpers. Verify pin 1, signal direction, supply voltage and ground at both ends of every cable. A mechanically fitting connector is not proof of electrical compatibility. If a host pin mapping or current allocation remains unresolved in the design record, do not connect the board until it is resolved.
See current review. Retain isolated single-channel relay topology; conditional V1 row58 indicator resistor already applied in retained v15; no new version Current selected v15; retained native/stock/physical qualification limits remain explicit.
Use the configuration and firmware contract for the exact selected revision. Do not copy another module’s socket assignments or assume that an unused pin is available. First-article work must verify source selection, reset/unplug behavior, cable orientation and the actual load or sensor interface before normal operation.
The following are requirements for the next design iterations; this page does not claim they are already fitted:
Documentation route: smoothieware.org/extensions/single-channel-dc-mechanical-relay.
The 2026-10-11 upgrade program has saved additional candidates v16, v17, v18. These studies preserve the historical design described above. Their connector, LED, mechanical and protection changes are revision-specific and remain unqualified.
See the per-board changes, failures and remaining work and mandatory family specification. Use the source hash and native check for the exact candidate being reviewed; do not infer hardware ratings from a rendered population.
The three additional revisions are v16, v17, v18. They are engineering studies; saved CAD and renders do not release the hardware. The latest candidate is described below. Older baseline notes above remain historical.
70c527e936a4fb0138d5b0a89f870615d7c5a788f9af3a013b31f16cd6eea37c.JST_PH_B3B-PH-K_1x03_P2.00mm_Vertical. Fit only the selected population; check its pin map and voltage in the design record.Applicable protection, current-path, thermal, pinout, cable access and physical tests remain open wherever the linked board record has not verified them. A zero native-error count does not close those gates.
Protected source v19; current PCB SHA-256 eb30aab068748b8def81ea3c2977c4ca74525ee68629062322b1daef90a4f149. Fresh checks: zero enabled errors/opens/parity/ERC findings; 1 PCB warnings. Electrical geometry, project rules and 98 historical files unchanged. Verified 120 model entries, 17 exports and 12 current population views, all inspected. Full documentation URL readable. Inherited native warnings and enabled-rule exclusions remain explicit Physical/thermal/current/connector-fit qualification open No priced or area savings established by annotation candidate.