Current Sensor¶
The alternator current sensor is a clamp: the battery cable (or alternator output cable) passes through its jaw, uncut. No splicing, no shunt, no connection to the high-current path at all.
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.
Mounting¶
- 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 — the arrow on the sensor body indicates positive current flow direction.
- Close and secure the jaw.
Wiring¶
The sensor connects with the green 4-pin screw-terminal plug (shown in the photo) — the same connector family as the regulator board. Run a Cat6 ethernet cable (one end cut off) from the sensor back to the regulator; its conductors come from Cable 1 (the right RJ5 port, alternator side):
| Sensor pin | Cable 1 wire | Signal |
|---|---|---|
| 1 | Blue/White | +5 V supply |
| 2 | Brown | GND |
| 3 | Brown/White | Vout (signal to regulator) |
| 4 | Brown | GND |
The sensor's two GND pins are internally common, so the single Brown ground wire serves both — land it on either terminal (or jumper the two). The complete pinout for all four cables is in Data Cables & Pinout.
Confirming it works¶
Power the regulator and open the dashboard. With the engine off, alternator current should read near zero. With the engine running and the alternator charging, the reading should be positive — if it reads negative while charging, the cable is passed through the jaw backwards; flip the sensor or re-route the cable to match the arrow.
Specifications, output scaling, and how the sensor works: Hardware → Sensors → Current Sensor.