Simulators

A single-zone air handler as a live DDC graphic — economizer dampers, hot-water coil, two DX stages — with the function-block program that runs it one tab away. Force sensors, override points through a real priority array, and watch the screen tell on the machine.

A DX fan coil on the same workbench — a smaller machine that leaves the whole control chain readable. Load a sample sequence or wire your own from a blank sheet, then stage cooling, break the fan proof, and chase the fault from the graphic into the logic.

A step-response simulator — gain · reset · rate (or Ti·Td / proportional band), preset tunings, a PV-vs-setpoint plot, and a symptom → tuning-move cheat sheet.

Practice navigating a generic drive's parameter tree on a clickable keypad — feel the run-source / speed-source gating before you're at a real drive. Paired with the VFDs explainer.

A graphical wiresheet sandbox — drop logic, math, timer, and PID blocks, wire them up, and watch a control sequence run live. Worked examples built in. Paired with the Function-Block Basics explainer.

A live parallel plant — demand rides a day-load curve while a configurable sequence stages units up and down, rotates the lead three ways, injects a fault, and logs every move. Paired with the Equipment Staging explainer.

Wire a generic DDC controller end to end — power it from a transformer, drop sensors, an actuator, and a fan, and click terminal-to-terminal. Land it right and points read live; land it wrong and it sparks, opens, or pops the fuse.

Build a hot- or chilled-water loop on an elevation — drop a plant, pump, coils, and valves, pipe them port-to-port, and watch real flow, head, and water temperature solve and propagate live. Three worked loops built in.

A live vapor-compression loop — turn airflow, charge, ambient, and metering superheat and watch suction, head, superheat, subcooling, and a starving coil react on manifold gauges and a live P-T strip. Pairs with the refrigerant lessons.