Help - KPJ Pump

⚡ Quick Start

Power the unit: 12-24V DC on VIN / GND terminals.
First boot starts AP: KPJ-Pump-Ctrl (password: kpjpump1)
Connect your phone/laptop to that network, open http://192.168.4.1
Tap WiFi in the nav bar, enter your network credentials, save.
After restart visit http://kpjpump.local (or check router for IP).
Go to Settings, choose mode, calibrate sensor, set setpoint.
Switch to AUTO mode on the dashboard. Done.

🔌 Hardware Connections

Terminal	GPIO	Function	Notes
VIN/GND	--	Power (12-24V DC)	Polarity protected. Use clean industrial PSU.
OUT1/COM1/NC1	27	Pump Relay (10A SPDT)	Connect pump to NO-COM for normally-open.
IN1	19	Float Switch (NPN pull-up)	Switch between IN1 and GND. LOW = tank full.
IN2	18	Fault Reset Button	Momentary switch to GND. Clears latched faults.
IN3	5	Flow Sensor (pulse)	Hall-effect meter. Signal to IN3, power from 5V/GND.
VI1	36	Pressure/Process Sensor	4-20mA or 0-10V selectable in Settings.
VO1/IO1	25	VFD Analog Setpoint	0-10V or 4-20mA via SW1 DIP switch on board.
A+ / B-	1/3/22	RS485 Bus	Modbus RTU. Add termination at end of cable run.

⚠ Never exceed 10A / 250VAC on relay contacts.

💡 NPN digital inputs are optocoupler-isolated. Industrial 24V sensors connect directly to IN1-IN4 with common/negative to GND.

⚙ Operating Modes

Pressure Control PRESSURE ▼

Maintains constant pressure using sensor feedback and pump start/stop.

Setpoint: Target pressure in your engineering units.
Hysteresis: Pump starts at setpoint - dead-band, stops at setpoint. Prevents rapid cycling.
VFD Output (VO1): Tracks setpoint as speed reference when enabled.
Float switch: Can act as overflow stop. Disable in Settings if not connected.

Supply Fill - Float Mode SUPPLY/FLOAT ▼

Simple level control. Pump runs when float says EMPTY, stops when FULL.

Float switch on IN1: LOW signal = FULL (NPN inversion)
Suitable for storage tanks, reservoirs, dams

Supply Fill - Timer Mode SUPPLY/TIMER ▼

Runs the pump for a fixed duration, a set number of times per day.

Set Run Duration (minutes) and Runs Per Day
Cycles are evenly spaced through 24 hours
Float switch pauses the pump without resetting the timer
Best for irrigation schedules or timed top-up systems

Supply Fill - Volume Mode SUPPLY/VOLUME ▼

Pumps a precise volume per cycle, measured by the flow meter.

Set Target Volume (litres) and Wait Interval (hours)
Requires flow meter on IN3 calibrated in Settings
Float switch pauses dispensing without losing count
Best for dosing, chemical injection, metered delivery

🛡 Safety System

Dry-Run Protection

Stops the pump if no water is detected while running. In Pressure mode: trips if pressure stays below Min Pressure for the Dry-Run Time. In Supply mode: trips if flow stays below 0.1 L/min (requires flow meter enabled). Only active while the pump relay is energised.

Overpressure Protection

Stops the pump if pressure exceeds the trip level for longer than the trip delay. Pressure mode only.

Sensor Fault Protection

Stops the pump if the analog input voltage is outside the expected range (open wire, short circuit, wrong type).

Auto-Restart

After a fault, waits the Restart Delay then retries automatically up to the configured number of Attempts. After 60 s clean running, the counter resets. Fault card shows RETRY 1/3, RETRY 2/3 etc.

⚠ Always investigate the cause before resetting. Repeated dry-run faults usually mean the water supply is exhausted or the inlet is blocked.

🌐 Remote Connectivity

MQTT Topics

Topic	Direction	Payload
`pump/status`	Publish (5s)	JSON with all live values
`pump/cmd/setpoint`	Subscribe	Numeric value
`pump/cmd/run`	Subscribe	`1` or `0`
`pump/cmd/mode`	Subscribe	`AUTO` or `MANUAL`
`pump/cmd/resetfault`	Subscribe	`1`

OTA Firmware Updates

In Arduino IDE go to Tools > Port and select the kpjpump network port. OTA password: kpjota1

Blynk Virtual Pins

Pin	Dir	Value
V0	R	Pressure
V1	R/W	Setpoint
V2	R/W	Pump (0/1)
V3	R/W	Mode (0=AUTO)
V4	W	Reset fault (send 1)
V5	R	Flow rate L/min
V6	R	Total litres
V7	R	State string

🔧 Troubleshooting

Symptom	Likely Cause	Fix
SENSOR_FAULT on startup	No sensor wired or wrong type	Check VI1 wiring or disable Sensor Fault in Settings
DRY_RUN immediately	Flow meter not connected	Disable Flow Meter in Settings > Connected Hardware
Pressure reads zero	Wrong calibration or wiring	Check VI1, verify voltages in Settings sensor section
Float not working	Wrong polarity or disabled	NPN: switch to GND. Enable float in Settings.
WiFi not reconnecting	Credentials not saved	Re-enter via AP mode (connect to KPJ-Pump-Ctrl)
Dashboard shows --	Browser cannot reach /status	Check WiFi, try http://kpjpump.local directly
Pump short-cycling	Hysteresis too small	Increase dead-band in Settings > Pressure Setpoint

KPJ Pump Controller

Dry-Run Protection

Overpressure Protection

Sensor Fault Protection

Auto-Restart

MQTT Topics

OTA Firmware Updates

Blynk Virtual Pins

KPJ Automation - Technical Support