OWB Monitor - Wiring

Wiring Diagram

                    LILYGO T-SIM7080-S3
                   ┌─────────────────────┐
       DC1 (3V3) ──┤ 3V3                 │
             GND ──┤ GND                 │
                   │                     │
          GPIO12 ──┤ 1-Wire ─────────────┼──[4.7kΩ]── DC1 (3V3)
                   │          │          │
                   │          ├── DS18B20 (House loop supply)
                   │          ├── DS18B20 (House loop return)
                   │          ├── DS18B20 (Barn loop supply)
                   │          └── DS18B20 (Barn loop return)
                   │                     │
            GPIO1 ──┤ SDA ───────────────── ADS1115 SDA
            GPIO2 ──┤ SCL ───────────────── ADS1115 SCL
                   └─────────────────────┘

    ADS1115 (addr 0x48)
   ┌──────────────────────────────────────┐
   │ VCC  ── DC1 (3V3)                    │
   │ GND  ── GND                          │
   │ ADDR ── GND                          │
   │ A0 ──┐  SCT-013-030 (house pump)     │
   │ A1 ──┘                               │
   │ A2 ──┐  SCT-013-030 (barn pump)      │
   │ A3 ──┘                               │
   └──────────────────────────────────────┘

Temperature Sensors - DS18B20

Four DS18B20 waterproof probes mounted on pipes using hose clamps with thermal paste. All four sensors share a single 1-Wire data line.

Sensor	Location	GPIO
House loop supply	Supply pipe - house loop	GPIO12 (1-Wire bus)
House loop return	Return pipe - house loop	GPIO12 (1-Wire bus)
Barn loop supply	Supply pipe - barn loop	GPIO12 (1-Wire bus)
Barn loop return	Return pipe - barn loop	GPIO12 (1-Wire bus)

Mounting

Apply thermal paste to the pipe at each sensor location
Place the DS18B20 probe flat against the paste
Secure with a hose clamp sized to the pipe OD

1-Wire Pull-up Resistor

The 1-Wire bus requires a 4.7kΩ pull-up resistor between the data line and 3.3V. Place it at the node end of the wire run, not at the sensor.

Current Sensors - SCT-013-030

Two CT clamps, one per pump. Each clamp goes around the hot conductor only - not both conductors in the cable. Clamping both conductors cancels the magnetic field and produces a null reading.

The pumps are plug-in. A custom monitored outlet box (planned) routes each pump’s hot conductor through a CT clamp before the outlet. The box plugs into a standard 120V outlet - no panel work required.

Sensor	Pump	ADS1115 Channel
House pump current	House loop pump	A0_A1 (differential)
Barn pump current	Barn loop pump	A2_A3 (differential)

SCT-013-030 Notes

The SCT-013-030 is the voltage output version with a built-in burden resistor. Output is 0-1V AC proportional to 0-30A. Connects directly to ADS1115 - no external resistor needed.

ADS1115 - I2C

ADS1115 Pin	LILYGO T-SIM7080-S3 Pin
VCC	DC1 (3V3)
GND	GND
SDA	GPIO1
SCL	GPIO2
ADDR	GND (address 0x48)

Power

5V Power supply and LiPo planned for the permanent install.