◈ MOUND SENSOR ARRAY — WIRING REFERENCE ◈

RASPBERRY PI ZERO W — UNIT 01 — WEST MOUND ST., COLUMBUS OHIO

▸ POWER CHAIN OVERVIEW

Panel 1 (10W, East) --[+]--> [Diode 1] --+ +--> Controller PV+ Panel 2 (20W, West) --[+]--> [Diode 2] --+ Panels (-) ------------------------------> Controller PV- Battery (+) --> INA219 VIN+ ... INA219 VIN- --> Controller BAT+ Battery (-) --------------------------------------> Controller BAT- Controller USB 5V OUT --> Pi Zero W power in (Load Mode 17 — Always On)
SOLAR PANELS (x2, PARALLEL) 10W + 20W · 12V
PANELFACINGNOTE
10WEastcatches morning tree gap
20WWestcatches evening tree gap
⚠ Each panel's (+) lead runs through its own 1N5822 Schottky blocking diode before joining the shared bus — prevents the sunlit panel from backfeeding the shaded one.
Negatives join directly, no diode needed.
NEWPOWA NPC-PHL10A PWM 10A CONTROLLER
TERMINALCONNECTS TONOTE
PV+/PV-Panel diode bussolar input
BAT+INA219 VIN-battery, via monitor
BAT-Battery (-)direct
USB OUTPi Zero W power inregulated 5V/2A
ℹ Battery Type set to SEL (Sealed/AGM). Load Mode set to 17 — Always On, so USB output survives a brownout without manual intervention.
LOAD terminals unused.
SLA/AGM BATTERIES (x2, PARALLEL) 12V LEAD-ACID
TERMINALCONNECTS TONOTE
+INA219 VIN+through power monitor
-Controller BAT-direct
ℹ Sourced free via workplace UPS supply.
Replaced 18650 Li-ion cells — SLA tolerates MOUND's real-world partial-charge cycling far better.
INA219 — POWER MONITOR I2C · 0x40
PINCONNECTS TONOTE
VCC3.3V — Pin 1power
GNDGround — Pin 6
SDAGPIO2 — Pin 3I2C data
SCLGPIO3 — Pin 5I2C clock
VIN+Battery (+)battery-side, in-line
VIN-Controller BAT+battery-side, in-line
⚠ Relocated from load-side (Pi 5V) to battery-side. Now reads true battery voltage and real charge (-) / discharge (+) current direction.
Library: adafruit-circuitpython-ina219
ADS1115 — ADC I2C · 0x48
PINCONNECTS TONOTE
VDD3.3V — Pin 1power
GNDGround — Pin 6
SDAGPIO2 — Pin 3I2C data
SCLGPIO3 — Pin 5I2C clock
ADDRGround — Pin 6sets 0x48
ℹ 4-channel ADC. Analog sensors connect to A0–A3
Library: adafruit-circuitpython-ads1x15
CAPACITIVE SOIL MOISTURE ANALOG → ADS1115
PINCONNECTS TONOTE
VCC3.3V — Pin 1power
GNDGround — Pin 6
AOUTADS1115 — A0analog signal
⚠ Disconnected wire reads as floating noise (large swings, sometimes negative) — not a real reading. Confirm connector is seated if values look erratic.
BME280 — ENV SENSOR I2C · 0x76
PINCONNECTS TONOTE
VCC3.3V — Pin 1power
GNDGround — Pin 6
SDAGPIO2 — Pin 3I2C data
SCLGPIO3 — Pin 5I2C clock
ℹ Board replaced Aug 2026 after corrosion damage from earlier enclosure water intrusion killed the original unit.
Library: adafruit-circuitpython-bme280
TSL2591 — LIGHT SENSOR I2C · 0x29
PINCONNECTS TONOTE
VIN3.3V — Pin 1power
GNDGround — Pin 6
SDAGPIO2 — Pin 3I2C data
SCLGPIO3 — Pin 5I2C clock
ℹ Wide dynamic range — full sun to near darkness
Reads: Lux (visible + infrared channels)
Library: adafruit-circuitpython-tsl2591
DS18B20 — SOIL TEMP PROBE 1-WIRE · GPIO4
PINCONNECTS TONOTE
VCC3.3V — Pin 1power (red wire)
GNDGround — Pin 6black wire
DATAGPIO4 — Pin 7yellow wire
⚠ 4.7kΩ pull-up resistor between VCC and DATA required
Reads as a file: /sys/bus/w1/devices/
FC-37 RAIN SENSOR ANALOG + GPIO
PINCONNECTS TONOTE
VCC3.3V — Pin 1power
GNDGround — Pin 6
AOADS1115 — A1rain intensity
DOGPIO17 — Pin 11yes/no rain
ℹ AO = analog rain intensity into ADS1115 A1
DO = digital trigger, adjust threshold via onboard pot
PI CAMERA REV 1.3 CSI RIBBON
INTERFACEDETAILNOTE
CSICamera connectorblue side → USB ports
RIBBONPi Zero adapter15→22 pin adapter req'd
ℹ 5MP OV5647 sensor · Noon keeper capture only
Command: rpicam-still -o ~/mound/photo.jpg

▸ I2C BUS ADDRESS MAP — GPIO2 (SDA) / GPIO3 (SCL)

0x40 INA219 · Battery Power Monitor
0x48 ADS1115 · ADC
0x29 TSL2591 · Light Sensor
0x76 BME280 · Env Sensor

▸ PI ZERO W — PIN ASSIGNMENTS

13.3Vall sensors
3GPIO2 SDAI2C bus
5GPIO3 SCLI2C bus
6GNDall sensors
7GPIO4DS18B20
11GPIO17Rain DO
CSICAMERAPi Cam Rev 1.3
PWRUSB-INController USB 5V

▸ RETIRED HARDWARE (pre-Aug 2026 rebuild)

Waveshare Solar Power Manager (D) — lithium-only, incompatible with lead-acid chemistry.
Waveshare 6V 5W solar panel — replaced by dual Newpowa panel array.
3x/4x 18650 Li-ion cells — chronic overnight power failure under tree shade; SLA/AGM tolerates MOUND's partial-charge cycling far better.