PHTS LVL-1

Features:

• Use ultrasonic sensor to measure distance
• Show level on the big fancy indicator
• Send levels and logs to szambo.tsaryk.com via Wi-Fi
• 24/7 monitoring
• Remote control via internet

Firmware

Consists of 2 modules: Arduino Nano and NodeMCU V3.

Hardware

• Arduino Nano^*
• NodeMCU V3^*
• Ultrasonic sensor: HC-SR04^* or AJ-SR04M^*
• Analog meter 0-5V
• Buttons/LEDs/etc

Design

Schematic diagram

Hosted on: OSHWLab/phts/lvl-1.

Deployment diagram

Usage

Indication

State	LED	Meter	Description
Normal	______________ (constantly off)	Actual level	Normally operational device
Warning	************** (constantly on)	Actual level	Level is reaching the maximum
Busy	*______*______ (slowly blinking)	- Starting up: progress bar (number on % bar) - Busy: not used	The device is starting up or performing an action
Failure	*_*_*_*_*_*_*_ (fast blinking)	Error code (number on m³ bar)	Operation failure. See the error code description in the table below

Errors

Code	Type	Description
1	Fatal	Ultrasonic sensor failure
2	Temporary	NodeMCU module communication failure
3	Temporary	Wi-Fi connection failure
4	Temporary	Unexpected HTTP response

• Fatal — will be indicated constantly until the failure is gone
• Temporary — will be hidden after 1 minute and back to the previous state