Dc resistance at temp ohm per km
dc_resistance_at_temp_ohm_per_km
DC resistance at operating temperature (ohm/km)
Scores if within ±3% of the reference value.
Computes the AC resistance of a power cable conductor at operating temperature by first correcting DC resistance from 20 deg C using R'(T) = R_20 * [1 + alpha_20 * (T - 20)], then applying the IEC 60287-1-1 skin effect factor ys to obtain R_ac = R_dc(T) * (1 + ys). Essential for cable thermal rating and power loss calculations in transmission and distribution systems.
with-tool: The model is given an executable Python calculator script.
Standards
One template produces many comparable benchmark tasks while keeping the scoring contract fixed.
01
The reusable contract shown on this page.
02
An archetype and site context are sampled.
03
Inputs may be hidden at harder tiers.
04
The model responds with the declared outputs.
Inputs the model receives, and the outputs it is scored on.
4 inputs
Included directly in every task prompt.
Dc resistance 20c ohm per km
dc_resistance_20c_ohm_per_km
DC resistance of conductor at 20 deg C
Operating temp c
operating_temp_c
Operating temperature of the conductor
Frequency
frequency_hz
System frequency
Sampled from the scenario and inferable from its description.
Conductor material
conductor_material
Conductor material
Derived from the archetype scenario. Hidden at hard difficulty.
3 outputs
dc_resistance_at_temp_ohm_per_km
DC resistance at operating temperature (ohm/km)
Scores if within ±3% of the reference value.
skin_effect_factor
Skin effect factor ys (dimensionless)
Scores if within ±5% of the reference value.
ac_resistance_ohm_per_km
AC resistance at operating temperature (ohm/km)
Scores if within ±3% of the reference value.
Each template is sampled at three tiers. Harder tiers may hide inputs, forcing the model to infer them from the scenario description.
All inputs given
Standard 50 Hz copper, moderate temperature, all params given
Frequency hz restricted to: 50
All inputs given
Any material and frequency, transmission-level conductors
Some inputs hidden
Conductor material hidden, agent must infer from context and resistance value
Hidden inputs
Prompt replacement text
The installation uses {{ archetype.description }} practices ({{ archetype.site_context }})
The exact instruction and parameter contract used to generate this task, pinned to the published library source.
/workspace
Teal lines show Jinja input conditions, not task visibility policy. A line renders only when that input or tool is visible.
1You are a senior electrical engineer specializing in power transmission and conductor design.2 3## Problem4 5Calculate the AC resistance of a conductor at its operating temperature, accounting for the temperature correction of DC resistance and the skin effect factor per IEC 60287-1-1.6 7## Given8 9| Parameter | Value | Unit |10|-----------|-------|------|11| DC resistance at 20 °C | {{ dc_resistance_20c_ohm_per_km }} | ohm/km |12{% if conductor_material is defined %}13| Conductor material | {{ conductor_material }} | - |14{% endif %}15| Operating temperature | {{ operating_temp_c }} | °C |16| System frequency | {{ frequency_hz }} | Hz |17{% if archetype_description is defined %}18 19### Installation Context20 21{{ archetype_description }}22{% endif %}23 24{% if tool_available %}25## Available Tool26 27A calculation tool is available at `/workspace/ac-resistance-temperature_calc.py`. Run it with:28 29```bash30python3 /workspace/ac-resistance-temperature_calc.py --help31```32 33You may use this tool to verify your calculations or compute values directly.34{% endif %}35 36## Required37 38Calculate the following:39 401. DC resistance at operating temperature (ohm/km)412. Skin effect factor ys (dimensionless)423. AC resistance at operating temperature (ohm/km)43 44## Applicable Standards45 46- IEC 60287-1-1 — Electric cables — Calculation of the current rating — Current rating equations and calculation of losses47- IEEE 738 — Standard for Calculating the Current-Temperature of Bare Overhead Conductors48 49## Constraints50 51- No internet access is available. Work from engineering knowledge and the provided tool.52- Use the IEC 60287-1-1 method:53 1. DC resistance at temperature: R_dc(T) = R_dc_20 * [1 + alpha_20 * (T - 20)]54 2. Temperature coefficient alpha_20: copper = 0.00393 /°C, aluminium = 0.00403 /°C55 3. Skin effect argument: xs^2 = 8 * pi * f * 1e-7 * ks / R_dc(T) where R_dc(T) is in ohm/m and ks = 1 for round stranded conductors56 4. Skin effect factor: ys = xs^4 / (192 + 0.8 * xs^4)57 5. AC resistance: R_ac = R_dc(T) * (1 + ys) — proximity effect yp = 0 for single isolated conductors58 59## Output Format60 61Show your step-by-step working in Markdown, including the temperature correction, skin effect calculation, and final AC resistance. At the end of your solution, include a JSON block with your final answers in exactly this format:62 63```json64{65 "dc_resistance_at_temp_ohm_per_km": <numeric_value>,66 "skin_effect_factor": <numeric_value>,67 "ac_resistance_ohm_per_km": <numeric_value>68}69```70 71Write your complete solution to `/workspace/output.md`.72 Each generated task is drawn from one of these realistic scenario bands.
Site contexts ground each scenario in a real locale the model can use to infer hidden values.
distribution_copper
Copper distribution cable at moderate temperature
distribution_aluminium
Aluminium distribution cable at moderate temperature
transmission_copper
Copper transmission conductor at elevated temperature
transmission_aluminium
Aluminium transmission conductor at high temperature
hunter-valley-transmission-transmission-copper-preview — hard difficulty, some inputs hidden.
Copper transmission conductor at elevated temperature. hunter-valley-transmission. Required outputs: dc_resistance_at_temp_ohm_per_km, skin_effect_factor, ac_resistance_ohm_per_km
Scenario context and visible inputs.
Executable tool: ac-resistance-temperature_calc.py
Inputs withheld at this difficulty.
Conductor material
conductor_material
Stand-in text in the prompt
The installation uses {{ archetype.description }} practices ({{ archetype.site_context }})
The scored JSON answer schema.
{
"dc_resistance_at_temp_ohm_per_km": <number>,
"skin_effect_factor": <number>,
"ac_resistance_ohm_per_km": <number>
}