# Temperature Sensor and Relay Selectors

Implemented 2026-09-19 as specification guides, with separate pure evaluators
and shared form/result rendering. Both work directly from file URLs with classic
scripts and no dependencies. No SKU database or model recommendation is included.

Results distinguish **Match**, **Mismatch** and **Confirm**. The overall status
prioritizes any known mismatch, then missing information, then matching entered
checks. Matching checks are not complete product approval. Blank numbers remain
unknown, malformed numbers are errors, and editing hides stale results.
Example buttons load explicitly fictional demonstration specifications.

## Temperature Sensor Selector

Inputs: room/duct/outdoor/pipe-surface/immersion application, required range and
sensor-only accuracy, BAS input profile, available conductors and optional probe/
environment notes. Compare a candidate's curve/signal, installation form,
range, accuracy and required conductors. Active candidates also expose available
AC/DC supply and the candidate's accepted supply type and voltage interval.
°C/°F switches preserve temperatures and convert accuracy as a difference.

Supported profiles: 10k Type II, Type III, Pt1000/1k Pt 385, 1k Pt 375,
0–10 V, 4–20 mA, unknown 10k curve and completely unknown. Exact profiles must
match. Unknown 10k versus Type II/III is unresolved, while unknown 10k versus
an RTD or active signal is a known mismatch. Unknown profiles never pass.
Matching a configured profile does not audit all capabilities of a BAS input.

Candidate range must cover the full required interval. A single known endpoint
can prove a mismatch; missing endpoints cannot prove a match. Accuracy compares
absolute ± sensor errors over the required interval, not total measurement chain
accuracy. Conductor count is only a count check, not wiring/RTD topology approval.
Power checks compare declared type and interval; a powered BAS loop input can be
entered as available DC supply. Actual voltage-signal loading, current-loop burden
and available supply current remain manufacturer checks. Passive elements do not
use the external transmitter power fields.

No generic curve temperature range, probe length, accuracy or weather rating is
invented. Actual assembly data must be entered. Probe/environment notes are
retained in the specification summary and are not automatically certified.

## Relay Selector

Inputs distinguish powered AC/DC output from a dry contact plus an external
coil supply. Compare coil nominal AC/DC voltage, steady and maximum pickup
consumption, and DDC continuous/pickup limits. Coil input supports mA/A and
VA (AC) or W (DC), converted using the candidate rated voltage. Unknown voltage
prevents power-to-current inference. DDC capacity is entered in mA, including
manually converted VA/W where appropriate. Unknown ratings are never inferred
from the other steady/peak rating. Input currents are maxima; pickup/inrush below
the steady value is rejected as inconsistent.

Nominal voltage is compared exactly; the guide does not invent manufacturer
pickup/hold tolerances. Current comparison requires the user's confirmation that
the DDC ratings apply to the actual coil duty. Dry contacts do not supply power.
External source capacity, shared output limits, AC frequency, triac leakage and
minimum load, suppression/polarity and pickup duration remain explicit checks.

The contact side records AC/DC voltage, resistive/inductive/electronic load,
running/inrush current and required NO/NC/SPDT/DPDT arrangement. Applicable
switching and making current ratings must be confirmed for this precise voltage,
category, contact and duty. Independent maximum voltage/current values and
resistive-only ratings cannot establish an inductive rating. No arbitrary
derating or inrush multiplier is used. SPDT covers a single NO or NC requirement;
DPDT also covers SPDT. Extra poles operate together, not independently.

Mounting is recorded as a requirement; socket compatibility, switching life,
minimum load and the complete assembly are checked separately. No safety-relay,
motor-starter, protection or electrical-code design is performed.

## References and rule basis

- [OMRON general-purpose relay guidance](https://www.ia.omron.com/product/cautions/36/safety_precautions.html):
  coil supply/frequency, contact load-dependent ratings, switching capacity and
  socket/application checks. Used for distinctions, not product ratings.
- [Kele technical reference](https://www.kele.com/content/technical-reference):
  BAS sensing and transmitter context. No Kele product performance is assumed.
- [Sensor curve documentation](temperature-sensor-lookup.md): BAPI Type II/III and
  platinum 375/385 reference identities already used by the resistance lookup.
  The selector does not transfer lookup intervals into assembly operating ratings.

Rules are explicit comparisons of user-entered specifications, not inferred
brand compatibility. Numerical bounds live in `selection-common.js`: temperature
−273.15 to 1000°C; accuracy greater than 0 through 100°C; voltage greater than
0 through 1000 V; current 0 through 1000 A; conductor counts 1 through 12.
These are tool limits, not equipment ratings or recommended design values.

## Verification

`node tests/selection-tools-tests.cjs` covers pure checks and actual-page DOM
interaction. `node tests/run-node.cjs` covers site references and directory wiring.
The Node adapter is not a browser. Actual browser rendering, native controls and
console verification remain pending under the known file-URL tool restriction.