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Engineering Disciplines
Engineering Learning Studios
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Design tools, 3D viewers, articles, and downloads — all organized by engineering discipline.
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Fire Alarm Systems2 Live
Design tools · 3D apps · articles🌡️
HVAC SystemsLive
Design tools · 3D apps · articles⚡
Electrical Systems2 Live
Design tools · 3D apps · articles📡
Radio CommunicationsLive
Design tools · 3D apps · articles⚙️
Mechanical SystemsLive
Design tools · 3D apps · articles🏢
Enterprise IT NetworksLive
Design tools · 3D apps · articles🤖
AI Engineering StudioLive
Design tools · 3D apps · articles📊
AI and Data Science StudioLive
Design tools · 3D apps · articles🚿
Plumbing SystemsLive
Design tools · 3D apps · articles🧯
Fire SuppressionLive
Design tools · 3D apps · articles🏗️
Civil & Structural StudioLive
Design tools · 3D apps · articles🛰️
SCADA & Industrial ControlsLive
Design tools · 3D apps · articles🛡️
Cybersecurity & OT SecurityLive
Design tools · 3D apps · articles🏙️
Smart BuildingsLive
Design tools · 3D apps · articles☀️
Renewable EnergyLive
Design tools · 3D apps · articles🎥
Physical SecurityLive
Design tools · 3D apps · articles💻
Software Engineering & CloudLive
Design tools · 3D apps · articles📐
BIM, CAD & Digital DesignLive
Design tools · 3D apps · articles📈
Industrial & Systems EngineeringLive
Design tools · 3D apps · articles⚗️
Chemical & Process EngineeringLive
Design tools · 3D apps · articles💧
Environmental & Water ResourcesLive
Design tools · 3D apps · articles🔬
Materials Science & MetallurgyLive
Design tools · 3D apps · articles🚀
Aerospace EngineeringLive
Design tools · 3D apps · articles🎓
STEM Learning StudioLive
Design tools · 3D apps · articles🛠️
Engineering SoftwareLive
Design tools · 3D apps · articles🦾
Robotics & AutomationLive
Design tools · 3D apps · articles🧩
Semiconductor & ElectronicsLive
Design tools · 3D apps · articles🧭
MechatronicsLive
Design tools · 3D apps · articles🎮 3D Viewers, Designers & Simulators
Interactive 3D Tools & Simulators
131+ interactive 3D viewers, system designers, and live simulators across every engineering discipline — real, working tools, not screenshots.
Power Substation 3D
HVAC 3D
Fire Alarm 3D
Popular Engineering Tools
Interactive engineering tools
Online calculators, simulators, and design tools.
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Electronic Circuit Simulator
Build & solve DC circuits online (nodal analysis)🧮
NEC Load Calculator
NEC 220 service & feeder load calc📉
Voltage Drop Calculator
Conductor sizing per NEC 210.19⚡
Arc Flash Calculator
IEEE 1584 incident energy & PPE🌡️
HVAC Cooling Load
Block load & tonnage (Manual J)🌀
Duct Sizing
Equal-friction duct sizing💧
Sprinkler Hydraulics
NFPA 13 density/area demand🔋
Fire Alarm Battery Calc
NFPA 72 secondary power sizing🏗️
Structural Beam Calculator
Reactions, shear & moment diagrams📐
Commercial Electrical Designer
Full NEC 220 commercial design + reports📡
Radio / DAS Designer
In-building DAS link budget & BDA sizing🛰️
SCADA Architecture Explorer
Interactive 3D Purdue-model SCADA systemFeatured reading
Editors' picks — start here
Technical Articles
Learn from practicing engineers
790+ free technical guides — NEC code, HVAC design, AI engineering, structural analysis, and more.
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NEC Electrical Code: A Practical Guide
How to read and apply NFPA 70 on real projects🔥
Fire Alarm System Design Fundamentals
NFPA 72 initiating devices, NACs, and annunciation🌡️
HVAC System Design Basics
Air-side vs. hydronic systems, loads, and duct sizing🤖
How Large Language Models Work
Transformers, attention, tokenization, and inference☀️
Solar PV — How It Works
Panels, inverters, string sizing, and NEC Article 690🔒
Cybersecurity Fundamentals — CIA Triad
Confidentiality, integrity, availability, and NIST CSF🏭
Modbus RTU & TCP Protocol Guide
Register mapping, function codes, and industrial wiring⚙️
PE Mechanical Exam — Complete Guide
Exam format, NCEES reference, and study strategy🏙️
BACnet Building Automation Protocol
Objects, services, MS/TP vs IP, and BAS integration
Available on Apple Books
69+ engineering reference books
Practical guides and PE/FE/NICET exam prep — electrical, mechanical, civil/structural, fire alarm, SCADA, AI, and BIM/Revit.
Certificate-style courses
Professional Programs
27 programs of 18 to 27 modules each, with interactive lessons, labs, calculators, practice problems, real-project case studies and a certificate of completion.
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Applied Electrical Engineering
24 modules: NEC design, load calcs, protection and coordination, with project calculators and a certificate.🏗️
Applied Civil & Structural Engineering
27 modules from structural analysis and foundations to code-based design, plus 7 design projects.🔥
Fire Alarm Design
23 modules: NFPA 72 design, battery and voltage-drop calculators, and 8 real-project case studies.🌡️
Applied HVAC Engineering
25 modules: psychrometrics, load calcs, duct and pipe sizing, with interactive widgets.⚙️
Applied Mechanical Engineering
24 modules: beams, gears, shafts, pumps and reliability, with labs and a conveyor project.🚀
Applied Aerospace Engineering
25 modules: aerodynamics, propulsion, orbits and rockets, with CubeSat and rocket sizing projects.🩺
Applied Biomedical Engineering
25 modules: device regulation, risk files, biosignals and sterilization, with battery sizing and biosignal front-end projects.🛡️
Industrial & Enterprise Cybersecurity
18 modules and 3 real-project case studies across IT and industrial OT/ICS security.More to explore
Drawings, free courses and code updates
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Engineering Illustrations Gallery
910+ labeled drawings in electrical power, OT cybersecurity, fire alarm and PLC/SCADA. Browse thumbnails by subject.🎓
Free Learning Resources
Free courses, tutorials and guides from universities, nonprofits, public agencies and technology companies, with the owner and what is free on each card.📜
Standards & Codes
The editions we track, what changed, and the organizations behind NFPA, IEEE, ASHRAE, ICC and other codes and standards.🤖
AI Digest
Current AI news for engineers: new models, agents and engineering software, updated regularly.Adjust real controls. Watch the physics respond.
Interactive Simulator Labs
Interactive simulators across engineering, AI & computing, science & math, and business — included with the All-Access Pass.
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AC Generator 3D Simulator
Spin a coil between magnetic poles and watch induced voltage and flux plotted live.❄️
Refrigeration Cycle Simulator
R-410A pressure-enthalpy diagram with live COP and EER.🔌
Power Transformer 3D Simulator
Explore the core, windings and cooling of a power transformer.⚙️
Three-Phase Induction Motor
Rotating field, slip and torque in 3D.🔥
Elevator Recall Simulator
Fire alarm Phase I recall sequence, step by step.🎛️
PID Control Loop Simulator
Tune Kp, Ti and Td on a live process trend.🖥️
Hot/Cold Aisle Containment
Data center airflow in 3D.☀️
Solar Panel I-V Curve
Irradiance, shading and bypass diodes.🌐
Network Failover Simulator
Dual-WAN detection and route switchover.🤖
Forward Kinematics Simulator
Joint angles to tool position.🔮
Bloch Sphere Simulator
Single-qubit state visualization.🔦
Total Internal Reflection
Find the critical angle interactively.