Current Sensor¶
Part: QNHCK1-21 — Open Loop Hall Effect Current Sensor (300 A version)
Open-loop, dismountable hall effect sensor. Galvanically isolated output. Measures DC, AC, or pulsed current. The primary conductor (battery cable) passes through the jaw — no cutting or splicing required.
Keep this dry
This sensor has no weatherproofing. Mount it in a dry location — inside a battery box, electrical panel, or enclosure. Do not expose to bilge splash, condensation, or any moisture.
Specifications (300 A version)¶
| Parameter | Value |
|---|---|
| Rated current | 300 A DC |
| Measure range | ±300 A |
| Output voltage | 2.5 V ± 2 V |
| Supply voltage | +5 V (±5%) |
| Power consumption | ≤ 20 mA |
| Galvanic isolation | 2.5 kV |
| Accuracy | ≤ 1% |
| Response time | ≤ 3 µs |
| Bandwidth | DC – 10 kHz |
| Operating temperature | −25 to +85 °C |
Output scale: 0 A → 2.5 V midpoint. Full positive (300 A) → 4.5 V. Full negative (−300 A) → 0.5 V. Linear across the full range.
Connector and Wiring¶
The sensor uses the same 4-pin 5.08 mm pitch screw-terminal connector as the regulator board.
| Pin | Signal |
|---|---|
| 1 | +5 V supply |
| 2 | GND |
| 3 | Vout (analog signal to regulator) |
| 4 | GND |
Wiring from the regulator to the sensor uses a Cat6 ethernet cable with one end cut off. Pin mapping and wire color assignments are covered in Connectors & Wiring.
Installation¶
- Choose a dry, protected location close to the battery or shunt point.
- Route the battery cable (or alternator output cable) through the sensor jaw. Current direction matters — arrow on the sensor body indicates positive current flow direction.
- Close and secure the jaw.
- Connect the 4-pin plug to the sensor.
- Run the Cat6 cable back to the regulator and terminate at the corresponding sensor input connector.