⚡ Lightning Protection Planner V3.0

10-line guide

1. Upload map — drag an image onto the canvas or use the Image button. Adjust transparency with the slider.
2. Set scale — click Set scale, click two points anywhere on the map, enter the real distance (in meters or feet, matching the active unit mode). All distances are then calculated correctly. Use Measure (next to Set scale) to read the distance between any two points without changing the scale.
3. Place components — select a type in the toolbar, click on the map. LSP and CTRL/interface automatically snap to an existing 2-Wire.
4. 2-Wire/monocable cables — connects FD tech+ 110, EasyGuard, FD tech+ 201 / 401 / 601, SDI-12, SDI110, LSP and CTRL/interface. Click 2-Wire/monocable, click A, click B. Add waypoints by clicking empty space along the way. Every dead-end must be an LSP or a grounded decoder.
5. Valve cables — connects a decoder to a valve. Maximum length depends on the wire size (Size dropdown — both mm² and AWG sizes available regardless of unit mode): 1.5 mm² = 100 m, 2 mm² = 133 m, 2.5 mm² = 166 m, 16 AWG = 88 m, 14 AWG = 139 m, 12 AWG = 220 m. Lengths display in feet when Imperial mode is active.
6. Grounding — EasyGuard and FD tech+ 201 / 401 / 601 have built-in LSP: double-click to ground ⏚ (green border). A grounded source protects all FD tech+ 110 decoders within 150 m on 2-Wire. SDI-12 and SDI110 do not need LSP.
7. Rules & warnings — red tags = violations, amber tags = within 10 % of a limit (early warning). Red dashed cables exceed the maximum distance. Components in error get a small red ⚠ triangle above them (the icon itself stays its original colour). Click a red violation to pan to and pulse-highlight the component on the map. All violations are exported to PDF.
8. Voltage drop (CTRL/interface) — click Voltage Drop. Loop vs Star is auto-detected: Loop uses total cycle length with R = L × (Ω/km)/2 (parallel return); Star uses farthest path × 2. Fill in Ohm/km (or pick a cable from the preset dropdown) and active outputs (15 mA per output, e.g. fully active D6 = 90 mA). Only decoders on the critical path (and branches off it) are counted; sibling first-level branches off CTRL/interface are ignored. Result must be ≥ 25 V. Toggle the critical path indicator on the map.
9. Select, copy, delete, undo — click to select, drag for selection box, Ctrl+click to add. Ctrl+C / Ctrl+V copies the selection together with any cable whose both endpoints are inside the selection. The pasted copies are standalone — no connection back to the original layout. Press Delete or Backspace to remove the entire selection in one go. Ctrl+A selects all. Ctrl+Z undo, Ctrl+Y (or Ctrl+Shift+Z) redo, up to 50 steps.
10. Units, dark mode & PDF — toggle Metric (m) ↔ Imperial (ft) with the button next to ? Help; the change applies to map labels, validation messages, the Voltage Drop panel, the Set-scale prompt and the PDF. UI follows the browser/OS dark-mode setting automatically. Save exports JSON, Load restores it, Download PDF exports the map + voltage calculation + any rule violations.

Components

Cable types

Lightning protection rules

• FD tech+ 110 must have a grounded source within 150 m on 2-Wire — either a standalone LSP, a grounded EasyGuard / FD tech+ 201 / 401 / 601, or the CTRL/interface (which always has its own ground).
• EasyGuard, FD tech+ 201 / 401 / 601 have built-in LSP and are considered grounded if they are either themselves grounded (double-click ⏚, ground rod symbol shown) or within 150 m of another ground source on the 2-Wire (green border, no rod symbol). A built-in-LSP decoder with neither is shown with a red dashed border and produces a violation.
• SDI-12 and SDI110 require no LSP.
• A grounded source protects everything within 150 m measured along the 2-Wire network (not straight-line distance).
• Valve cables may be at most the maximum for the selected wire size (Size dropdown — defaults to 1.5 mm² / 100 m).
• All components must have at least one cable.
• CTRL/interface must be connected on 2-Wire.
• When at least one CTRL/interface is on the map, every decoder, input and LSP must be reachable from a CTRL via the 2-Wire graph. If no CTRL has been placed yet, components can sit unconnected (useful for sketching sub-sections before adding the controller).
• Every 2-Wire dead-end must be a standalone LSP or a self-grounded built-in-LSP decoder (EasyGuard or FD tech+ 201 / 401 / 601 with its own ⏚). Being merely covered by another ground within 150 m is not sufficient at the termination point — the surge must be shunted to ground at the dead-end itself.

Voltage drop calculation

• System voltage: 42 V — minimum at far end: 25 V. The status text reads "If the voltage is above 25 V, the system is operational."
• Topology auto-detected:
  • Loop: 2-Wire connects back to itself (cycle through CTRL/interface). R = (total loop length ÷ 1000) × ((Ω/km) ÷ 2). The two halves of the loop carry current in parallel for the round trip. Branch spurs off the loop add decoders to the current count but do not extend the loop length.
  • Star: 2-Wire branches outward, no return path. R = (farthest distance ÷ 1000) × Ω/km × 2. Use the radio buttons to choose worst-case (All at end) or typical (Evenly distributed — the displayed cable length is the full distance, but the calculation uses half).
• Ohm/km field: type any value, or pick a preset from the Cable preset dropdown next to it. Presets include 1.0–4.0 mm² and 10–18 AWG with their typical Ω/km values; both groups are available regardless of unit mode.
• Standby current: 0.3 mA per decoder counted on the critical path.
• Active outputs: 15 mA per active output. A fully active FD tech+ 601 (6 outputs) draws 90 mA. Enter the total simultaneous active outputs in the Active outputs field on the Voltage-Drop bar.
• Critical-path counting: only decoders along the critical path (and any sub-branches off that path) are counted. Sibling first-level branches off CTRL/interface are ignored — their current does not flow through the critical resistance.
• Manual decoder count: override the auto count for calculation only (e.g. future-capacity planning).
• Critical path indicator: a pink overlay on the map highlights the longest 2-Wire route (Star) or the closed loop (Loop). Toggle on/off via the checkbox in the panel.
• Formula: V-drop = I × R, V@end = 42 − V-drop, must be ≥ 25 V.
• All numeric outputs (currents, R, V-drop, V@end, distances) are shown to 1 decimal place.

End-of-2-Wire rule

• Every 2-Wire dead-end (a node with only one 2-Wire connection, excluding CTRL/interface) must be either a standalone LSP or a self-grounded built-in-LSP decoder (EasyGuard / FD tech+ 201 / 401 / 601 with its own ⏚). The "within 150 m of a ground" allowance does not apply at a dead-end — the cable must terminate at a component that physically shunts surges to ground.

Select, copy and paste

Canvas navigation

Save, load and PDF

• Save — exports the entire layout as a JSON file (components, cables, map image, scale, voltage-calc settings, valve wire size and metric/imperial unit preference).
• Load — restores a saved layout. Supports files from V1, V2 and V3.
• Download PDF — exports the map at native image resolution with a legend, plus a voltage calculation page and any rule violations as extra pages. Distances on the PDF use the active unit mode (m / ft).
• Scale is saved in the file — distances are correct when reloaded regardless of which unit mode the file was saved in.

UI features

• Dark mode — follows your browser / OS preference automatically (prefers-color-scheme). No manual toggle needed.
• Critical path indicator — when a CTRL/interface is present, the longest 2-Wire path from CTRL/interface is highlighted on the map (the path the voltage-drop calculation uses for Star topology). Toggle on/off via the checkbox in the Voltage Drop panel (on by default).
• Validation margin — amber warnings appear when a value is within 10 % of a limit (cable length, voltage drop, etc.) so you can react before it becomes a hard violation. Red = violation, amber = early warning.
• Measure tool — read the distance between any two points without altering scale. Result stays on the canvas until cleared.
• Unit toggle — the button next to ? Help switches the whole UI between 🌐 Metric (meters) and 🇺🇸 Imperial (feet). All on-canvas distance labels, validation messages, the voltage-drop panel, the PDF export and the Set-scale prompt switch units accordingly. Both mm² and AWG cables are available in either mode (the toggle only reorders which group is listed first).
• Ohm/km presets — pick a standard cable from the dropdown to fill the Ohm/km field, or type any custom value. Available in both groups: 1.0–4.0 mm² and 10–18 AWG.
• Number precision — all calculated values are shown to one decimal place.
• Component summary — a strip above the violations lists how many of each model (FD tech+ 110, EasyGuard, FD tech+ 201 / 401 / 601, SDI-12, SDI110) you have placed, the total decoders/inputs/CTRL count and how many ground rods or plates are on the map. Each CTRL/interface contributes its own dedicated ground; decoders contribute only if they have been explicitly grounded (double-clicked). Decoders that are merely protected through another grounded source are not counted here.
• Clickable violations — click any red error tag to pan to and briefly pulse-highlight the offending component on the map.
• Show/hide valves — the Show valves checkbox in the settings row toggles valves and valve cables on or off, useful for de-cluttering the map when reviewing the 2-Wire layout.
• Auto-connect valves — the button next to Show valves wires every unconnected valve to its nearest decoder that (a) is within the active valve-wire-size's allowed distance and (b) still has output capacity left. Use it to bulk-wire a freshly-placed cluster of valves; valves outside range or with no decoder capacity are reported in the flash message.
• Optimize 2-Wire — replaces the current 2-Wire layout with the shortest tree from the CTRL/interface that reaches every decoder, input and LSP (minimum-spanning-tree on straight-line distance). Existing 2-Wire cables and any orphaned junctions are removed; valve cables are untouched. The flash message reports the new cable count and total length. Undo with Ctrl+Z if you don't like the result.
• Component colours — every model has a distinct colour: FD tech+ 110 and EasyGuard share light green (both 1-output siblings), FD tech+ 201 is teal, FD tech+ 401 is royal blue, FD tech+ 601 is magenta. Inputs use their own palette: SDI-12 amber, SDI110 violet. Valves are gray. Components always keep their original colour — when in error a small red ⚠ triangle is drawn just above the icon. The CTRL/interface is enlarged with a cyan glow, a yellow ring and its own ground rod symbol so it stands out on busy maps.
• Align & distribute — select 2 or more components (drag-box or Ctrl+click) and use the Align button group in the toolbar to line them up: left, vertical centre, right, top, horizontal centre, bottom. With 3 or more selected, the last two buttons distribute the components evenly horizontally or vertically (the leftmost/topmost and rightmost/bottommost stay put; everything in between is spaced at equal intervals).