# Solar Halowerk Inverter & Cable Loss Calculator

> Solar Halowerk Inverter & Cable Loss Calculator is a paid API for AI agents from solar.halowerk.com, paid per call via x402, $0.002/call, status unknown (last checked 2026-09-14).

Calculates DC cable resistive losses and inverter efficiency losses for a solar power system given cable specs, inverter parameters, battery voltage, and load.

## Facts

- Endpoint: POST https://solar.halowerk.com/inverter-losses
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/solar-halowerk-inverter-cable-loss-calculator-e4bfa44d
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_wdImv2KegiqXwmiqpF73i

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability solar-halowerk-inverter-cable-loss-calculator-e4bfa44d -d '<json body>'
```

Example prompt: For my 24V solar system, calculate the cable and inverter losses when running a 600W load — the copper cable is 4mm² cross-section with a 3-metre one-way run, and my inverter is rated at 1200W with 93% peak efficiency and 15W idle draw.

## When to prefer this

Use this endpoint when you need to quantify DC-side resistive losses and inverter efficiency losses in a solar or off-grid power system, particularly when sizing cables or assessing real-world system efficiency. Prefer this over generic electrical calculators because it uses a three-part inverter efficiency model (idle + proportional + quadratic) calibrated to peak efficiency near half rated power, and doubles the cable run automatically.

## Known failure modes

- Missing required cable fields (length_m or cross_section_mm2) returns a validation error
- load_w outside range 1–100000 returns a 422 error
- battery_voltage_v not provided may result in incomplete voltage drop calculation
- Inverter rated_w below the specified load_w may produce nonsensical efficiency figures
- Floating-point precision limits for very small cross-sections or very short runs

## How this service works

Cable loss uses the DC resistance of the two-way run at twenty degrees Celsius; warm cable in a hot compartment carries roughly four percent more resistance per ten kelvin, which is not applied. Inverter loss follows a three-part model of idle draw, a proportional share and a quadratic share, fitted so that the stated peak efficiency is met near half of the rated power.

## Output

Returns calculated DC cable resistive loss (in watts and as a percentage voltage drop), inverter loss (modelled from idle draw, proportional share, and quadratic share), and likely total power drawn from the battery — allowing the caller to assess whether cable sizing is adequate and what the real-world system efficiency is at the specified load.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "cable": {
   "type": "object",
   "required": [
    "length_m",
    "cross_section_mm2"
   ],
   "properties": {
    "length_m": {
     "type": "number",
     "maximum": 200,
     "minimum": 0.1,
     "description": "One-way run; the calculation doubles it."
    },
    "material": {
     "enum": [
      "copper",
      "aluminium"
     ],
     "type": "string",
     "default": "copper"
    },
    "cross_section_mm2": {
     "type": "number",
     "maximum": 500,
     "minimum": 0.5
    }
   },
   "additionalProperties": false
  },
  "load_w": {
   "type": "number",
   "maximum": 100000,
   "minimum": 1,
   "description": "AC power drawn at the output."
  },
  "inverter": {
   "type": "object",
   "properties": {
    "idle_w": {
     "type": "number",
     "default": 15,
     "maximum": 500,
     "minimum": 0
    },
    "rated_w": {
     "type": "number",
     "default": 1200,
     "maximum": 100000,
     "minimum": 50
    },
    "peak_efficiency": {
     "type": "number",
     "default": 0.93,
     "maximum": 0.99,
     "minimum": 0.5
    },
    "efficiency_at_load": {
     "type": "number",
     "maximum": 0.99,
     "minimum": 0.3,
     "description": "Measured efficiency at this exact load, overrides the model."
    }
   },
   "additionalProperties": false
  },
  "battery_voltage_v": {
   "type": "number",
   "maximum": 1000,
   "minimum": 6
  },
  "max_voltage_drop_percent": {
   "type": "number",
   "default": 3,
   "maximum": 10,
   "minimum": 0.5
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/solar-halowerk-inverter-cable-loss-calculator-e4bfa44d/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from solar.halowerk.com](https://www.zero.xyz/host/solar.halowerk.com/llms.txt)