Dosing System Accuracy Test Bench

A compact desktop dosing system accuracy test bench for laboratory R&D and calibration, utilizing a peristaltic pump, ZK-SMC02 motor controller, and Zemic load cell with an HX711 amplifier powered by an AC multi-output DC power supply.

Executive Summary

This reference design defines the system architecture, critical component candidates, risk register, and validation path for Dosing Test Bench. It is a system-level design deliverable; verify critical claims with manufacturer evidence and prototype testing before production release.

Design Overview

Requirements Coverage

Requirement	Architecture coverage	Status
Precise fluid dosing using Kamoer KCPS200 peristaltic pump	MOTOR_CTRL	Covered
Motor control and speed regulation via ZK-SMC02 controller	MOTOR_CTRL, MCU	Covered
Weight measurement using Zemic L6N load cell and HX711 amplifier	SENSOR, MCU	Covered
Laboratory R&D calibration and data verification	MCU, POWER	Covered

Item	Details
Product Type	Dosing Test Bench
Key Functions	Precise fluid dosing using Kamoer KCPS200 peristaltic pump, Motor control and speed regulation via ZK-SMC02 controller, Weight measurement using Zemic L6N load cell and HX711 amplifier, Laboratory R&D calibration and data verification
Power Source	AC 110-220V
Connectivity
Size	compact desktop unit
Environment	indoor
Difficulty	Intermediate
Est. Time	6-8 hours

System Architecture

Power Topology: USB-C 5V → MCU 3.3V LDO

Module List

Module ID	Type	Name	Function	Voltage
POWER	POWER	USB-C Power Jack	Power input	5V
MCU	MCU	ESP32-WROOM-32	Main controller	3.3V

Power Tree and Signal Interfaces

From	To	Type	Interface / rail	Voltage
POWER	MCU	power	Power	-

Design Schemes

Dosing Test Bench ★

Key IC selection

main MCU

• Need: Wi-Fi/BLE connectivity for lab data logging, sufficient GPIOs for sensor and motor interfaces
• Class: 32-bit Wi-Fi/BLE Microcontroller SoC
• Shortlist: ESP32-WROOM-32, ESP32-S3-WROOM-1
• Pick: Select based on module availability, pinout requirements, and RF certification status.

weight measurement analog front-end

motor speed and driver interface

Risk register

ID	Area	Severity	Detail	Mitigation
r1	emi	high	The inductive switching noise from the ZK-SMC02 motor controller and peristaltic pump motor can couple into the highly sensitive, low-level analog signals from the Zemic L6N load cell and HX711 amplifier.	Ensure strict ground separation between the high-power motor loop and analog sensor circuitry, use shielded twisted-pair cabling for the load cell, and add RC filtering on HX711 input lines.
r2	power	med	USB-C power (typically 5V/500mA to 2A) may experience voltage sags when the peristaltic pump motor activates, causing brownouts on the ESP32 MCU.	Provide a separate power rail or adequate bulk capacitance (low-ESR electrolytic + ceramic decoupling) on the 5V rail, and consider powering the motor controller from an independent external supply.

Bring-up and Validation Plan

1. Power-off inspection and rail resistance checks
2. Current-limited first power-up; verify every rail before enabling loads
3. Validate interfaces and timing one subsystem at a time
4. Run thermal, fault-injection, EMC pre-scan, and endurance tests for the target environment

Key Components

2/2 modules matched to real parts. See the BOM tab for the full component table.

USB-C Power Jack (USB4105-GF-A)

The candidate's MPN and manufacturer exactly match the primary MPN and preferred criteria.

ESP32-WROOM-32 (ESP32-WROOM-32)

The candidate code 'ESP32-WROOM-32' is an exact match for the primary MPN, and the manufacturer is Espressif Systems.

Build Summary

• Difficulty: Intermediate
• Estimated time: 6-8 hours
• Tools required: Soldering iron, Multimeter, Wire strippers, Phillips screwdriver, USB-C cable, Hot glue gun

See the Build tab for the full step-by-step assembly guide.

Evidence and Limitations

• Confirm part parameters, certifications, and compatibility against current manufacturer documents.
• Treat industry compliance without test or certificate evidence as a compliance gap, not an approval.
• See Reference Images for visual artifacts and Build Guide for detailed assembly and bring-up steps.