Engineering Systems Toolkit

This app is the definitive visual reference for working engineers, technicians, students, and inspectors. Browse 477 professional-quality diagrams spanning 8 major engineering disciplines — all offline, all in one app. WHAT IS INSIDE 477 illustrations organized into 8 engineering categories: Electrical Systems — power distribution, panel wiring, conduit layouts, load centers Fire Alarm Systems — initiating devices, notification appliances, control panels, wiring HVAC Systems — air handling, duct networks, chilled water, refrigerant circuits BIM and Construction — floor plans, riser diagrams, coordination views, LOD references Enterprise IT — network topology, structured cabling, data center layout, TIA-942 PLC and Automation — ladder logic, I/O modules, PLC panels, field instrumentation SCADA and Controls — RTU diagrams, HMI screens, Modbus/DNP3 architecture, control loops RF and Radio Systems — antenna configurations, path diagrams, repeater systems, link diagrams GLOBAL SEARCH Search all 477 diagrams instantly by name across every category. One-tap category filter chips let you narrow results to a single engineering discipline in seconds. DIAGRAM OF THE DAY A fresh featured diagram appears on the home screen every day — automatically curated from all 8 disciplines. A new reference point every time you open the app. SHARE ANY DIAGRAM Send any illustration directly to colleagues, students, or inspection reports using the iOS Share Sheet — available from every diagram in the gallery. ENGINEERING CALCULATORS Each category includes a dedicated field calculator: Voltage Drop — NEC K-factor conductor sizing with pass/fail at 3% threshold Battery Standby — NFPA 72 battery Ah sizing for fire alarm panels HVAC — CFM airflow, cooling load in BTU/h and tons, duct sizing at target FPM BIM Space — multi-room gross/net area, GFA, and volume in imperial or metric IT Network — PoE budget (802.3af/at/bt) and IPv4 subnet calculator with CIDR PLC I/O — module count, chassis sizing, and scan time estimation RF Link Budget — FSPL, path loss, link margin with fading environment presets SCADA Timing — Modbus RTU frame timing, T3.5 gap, and DNP3 poll cycle load STANDARDS REFERENCE Built-in searchable reference covering NFPA 72, NEC, ASHRAE, ISO 19650, IEC 61131-3, IEC 62443, TIA-942, and ITU/FCC standards — filtered by engineering domain. KEY FEATURES Swipeable full-screen gallery — page through every diagram in a category Pinch-to-zoom — inspect fine detail on any illustration Favorites — star and collect your most-used diagrams Works fully offline — no internet connection required iPhone and iPad — optimized for all screen sizes and orientations Whether you are reviewing a design, studying for a certification, or troubleshooting a system in the field, this app puts 477 reference diagrams and professional engineering tools in your pocket.