LPG Gas Monitoring Device Design
Budget: $250 – $750 USD
Smart LPG Gas Monitoring & Safety Device
EVT Hardware Design – Complete Scope (Individual Engineer)
1. Project Objective
Design and validate an EVT-stage Smart LPG Gas Monitoring & Safety Device for residential and light commercial use, intended for future certification (EN 50194) and mass production for the Nepalese market.
Safety, reliability, and fail-safe behavior are non-negotiable.
⸻
2. Core Functional Requirements
• LPG gas leak detection (MQ-6 or equivalent)
• Cylinder “empty / low pressure” detection
• Local alerts: buzzer + visual indication
• ESP32-based controller (Wi-Fi support; EVT may operate offline)
• Optional 12V solenoid valve control
• Fail-safe behavior:
• On total power loss, gas must remain OPEN
• Primary power: 12V DC adapter
• Backup power: 2×18650 Li-ion cells with proper BMS
• Seamless mains → battery switchover
⸻
3. Engineer Responsibilities (Complete EVT Package)
Phase 1 – Architecture & Safety Design
• System block diagram
• Power tree and backup duration estimation
• Battery management and protection strategy
• Solenoid driver and isolation concept
• Risk analysis and safety notes
• Design assumptions documented
Deliverables:
• Architecture diagrams (PDF)
• Power budget summary
• Risk & mitigation notes
⸻
Phase 2 – Schematic Design
• Full schematics (MCU, sensors, power, charging, solenoid driver)
• Component selection (cost + availability conscious)
• Low-noise analog front-end for gas sensor
• Fail-safe logic and fault conditions
Deliverables:
• Complete schematics (PDF + source)
• Initial BOM
⸻
Phase 3 – PCB Layout (EVT)
• 2–3 layer PCB
• Proper creepage, clearance, and isolation
• EMI-aware layout
• Test points for EVT validation
• Designed for manufacturability
Deliverables:
• PCB layout files
• Gerbers
• Updated BOM
• Assembly notes
⸻
Phase 4 – EVT Support & Iteration
• EVT bring-up guidance
• Test and calibration procedure
• Review of EVT failures (if any)
• One design refinement iteration included
Deliverables:
• EVT test plan
• Calibration notes
• Design revision (if required)
• Final EVT report / recommendations for DVT
⸻
4. Out of Scope (Explicit)
• Firmware development (basic pin planning only)
• Certification testing or lab submission
• Mass production support beyond EVT
⸻
5. Expectations
• Clean, documented, manufacturer-ready design
• All IP belongs to the project owner
• Files must be transferable to third-party manufacturers
• Clear communication and progress updates
⸻
6. Target EVT Output
• 2–5 EVT prototype units can be fabricated using delivered files
• Design validated for:
• Power safety
• Sensor stability
• Fail-safe operation
• Manufacturability readiness
⸻
One sentence that defines the project
“This is a safety-critical EVT hardware design intended to move toward certification and mass production — not a hobby prototype.”
EVT Hardware Design – Complete Scope (Individual Engineer)
1. Project Objective
Design and validate an EVT-stage Smart LPG Gas Monitoring & Safety Device for residential and light commercial use, intended for future certification (EN 50194) and mass production for the Nepalese market.
Safety, reliability, and fail-safe behavior are non-negotiable.
⸻
2. Core Functional Requirements
• LPG gas leak detection (MQ-6 or equivalent)
• Cylinder “empty / low pressure” detection
• Local alerts: buzzer + visual indication
• ESP32-based controller (Wi-Fi support; EVT may operate offline)
• Optional 12V solenoid valve control
• Fail-safe behavior:
• On total power loss, gas must remain OPEN
• Primary power: 12V DC adapter
• Backup power: 2×18650 Li-ion cells with proper BMS
• Seamless mains → battery switchover
⸻
3. Engineer Responsibilities (Complete EVT Package)
Phase 1 – Architecture & Safety Design
• System block diagram
• Power tree and backup duration estimation
• Battery management and protection strategy
• Solenoid driver and isolation concept
• Risk analysis and safety notes
• Design assumptions documented
Deliverables:
• Architecture diagrams (PDF)
• Power budget summary
• Risk & mitigation notes
⸻
Phase 2 – Schematic Design
• Full schematics (MCU, sensors, power, charging, solenoid driver)
• Component selection (cost + availability conscious)
• Low-noise analog front-end for gas sensor
• Fail-safe logic and fault conditions
Deliverables:
• Complete schematics (PDF + source)
• Initial BOM
⸻
Phase 3 – PCB Layout (EVT)
• 2–3 layer PCB
• Proper creepage, clearance, and isolation
• EMI-aware layout
• Test points for EVT validation
• Designed for manufacturability
Deliverables:
• PCB layout files
• Gerbers
• Updated BOM
• Assembly notes
⸻
Phase 4 – EVT Support & Iteration
• EVT bring-up guidance
• Test and calibration procedure
• Review of EVT failures (if any)
• One design refinement iteration included
Deliverables:
• EVT test plan
• Calibration notes
• Design revision (if required)
• Final EVT report / recommendations for DVT
⸻
4. Out of Scope (Explicit)
• Firmware development (basic pin planning only)
• Certification testing or lab submission
• Mass production support beyond EVT
⸻
5. Expectations
• Clean, documented, manufacturer-ready design
• All IP belongs to the project owner
• Files must be transferable to third-party manufacturers
• Clear communication and progress updates
⸻
6. Target EVT Output
• 2–5 EVT prototype units can be fabricated using delivered files
• Design validated for:
• Power safety
• Sensor stability
• Fail-safe operation
• Manufacturability readiness
⸻
One sentence that defines the project
“This is a safety-critical EVT hardware design intended to move toward certification and mass production — not a hobby prototype.”