I. Introduction

The disinfection cabinet control board is the "brain" of the equipment, operating in a harsh environment of high temperature, high humidity, and chemical corrosion (ozone/UV). Its quality directly determines the disinfection efficiency, safety, and service life of the whole machine. This article details the standardized production process of the disinfection cabinet control board and the full-cycle quality control system, focusing on solving common problems such as corrosion, short circuits, and functional failures caused by harsh working conditions.

II. Standardized Production Process of Disinfection Cabinet Control Board

1. Pre-Production Preparation: Material Selection & Standardization

PCB Board Selection: Adopt high-TG (≥170℃) flame-retardant FR-4 board with thickened copper foil (1oz-2oz) to enhance moisture resistance and corrosion resistance; the board surface is treated with HASL (Hot Air Solder Leveling) or ENIG (Electroless Nickel Immersion Gold) to prevent oxidation.

Component Screening: Select industrial-grade components with high temperature and humidity resistance:

Capacitors: Use X7R/X5R ceramic capacitors (operating temperature -55℃~125℃) and solid aluminum electrolytic capacitors to avoid electrolyte leakage;

Relays: Choose high-temperature resistant relays (contact temperature ≥125℃) with load current ≥10A for driving heating tubes/ozone generators;

Sensors: Adopt waterproof NTC temperature sensors (IP65 rating) and corrosion-resistant water level probes.

Document Preparation: Formulate BOM (Bill of Materials), process flow charts, and welding parameters (temperature, speed) to ensure consistency in mass production.

2. PCB Manufacturing & Component Mounting

PCB Etching & Drilling: Use precision CNC drilling (hole diameter tolerance ±0.05mm) and chemical etching to ensure circuit accuracy; conduct 100% visual inspection for short circuits, open circuits, or burrs.

SMT (Surface Mount Technology):

Apply solder paste through a stencil (thickness 0.12-0.15mm) with uniform printing, no bridging;

Mount components (chips, resistors, capacitors) via high-precision placement machines (positioning accuracy ±0.03mm);

Reflow soldering: Use nitrogen reflow oven with temperature curve optimization (peak temperature 235±5℃, holding time 30-60s) to ensure solder joint reliability.

THT (Through-Hole Technology): For large components (relays, terminals), use wave soldering (temperature 250±10℃) with preheating to avoid cold solder joints; manually solder special components and inspect for solder bridging or insufficient solder.

3. Post-Soldering Processing: Waterproof & Moisture-Proof Treatment

Cleaning: Use ultrasonic cleaning with environmentally friendly flux remover to eliminate residual flux (corrosive to PCBs in high humidity); dry at 80℃ for 30 minutes to remove moisture.

Three-Anti-Coating (Conformal Coating):

Adopt automatic spraying of silicone or acrylic conformal coating (thickness 0.1-0.2mm) to cover the entire board (excluding connectors, key contacts);

Cure at 60℃ for 2 hours or room temperature for 24 hours to form a moisture-proof, dust-proof, and corrosion-resistant film;

For high-end models, use potting technology: Fill the control board with silicone potting glue (thermal conductivity ≥0.8W/(m·K)) to fully isolate steam and moisture.

Assembly: Install connectors, fuses, and fixing brackets; ensure the wiring harness is neatly arranged and fixed with cable ties to avoid short circuits caused by friction.

4. Testing & Aging: Functional Verification

Initial Functional Test: Power on each control board to test:

Basic functions: Key response, display, mode switching (high-temperature/ozone/UV);

Load test: Connect simulated heating tubes/ozone generators to verify drive capability;

Protection functions: Trigger over-temperature, water shortage, and door interlock protection to check alarm and shutdown responses.

Aging Test:

Place the control board in a high-temperature and high-humidity chamber (temperature 60℃, humidity 85%) for 48-hour continuous operation;

Simulate real working conditions (cyclic heating, disinfection mode switching) to screen out early failures (e.g., capacitor aging, solder joint fatigue).

Visual Inspection: Check for conformal coating bubbles, component damage, or loose connections; mark qualified products with batch numbers for traceability.