Panel Editor

The editor is the main screen in ElectroBoard, where you design your electrical panel. Here you add devices, configure the connections between them, set cables, and see check results in real time.

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Panel navigation#

The working area is an SVG canvas with DIN rails and devices. You can freely pan and zoom it.

On a computer:

• Mouse wheel — zoom to the cursor position
• Left mouse button + drag on the background — pan
• Space (hold) or the "Hand" tool (H) — pan without the risk of catching devices

On mobile:

• Pinch (two fingers) — zoom
• One finger on the background — pan

Adding devices#

New devices are taken from the "Components" palette on the left: click one to pick it "into your hand", or drag it onto a DIN rail.

On a computer:

1. The palette is visible by default. To hide or show it, use the button at the top of the tool column or *Ctrl+*; you can change the palette width by dragging its right edge
2. Use the search at the top of the palette (the / key) — it works by name, abbreviation, description, device parameters, and hints (for example, "Modbus", "gG", "RS485"). If you typed in the wrong keyboard layout, the palette notices and shows the results for the correct one
3. Or find the device in the relevant group — groups collapse, and each has a coloured mark and a device count. At the top are the "Favorites" (the star on a row adds a device to them) and "Recent" sections
4. The ⓘ button on a row opens the "About the device" card: what can be configured after placement, connection variants, the designation on the diagram
5. Click a device — it ends up "in your hand" (a hint appears at the bottom of the palette). Click a free place on a rail — the device is placed there. Esc cancels
6. Or drag the device onto a rail — it "snaps" to the nearest free slot

From the keyboard: Enter on a palette row takes the device into your hand; ←/→ — the neighbouring free place on the rail, ↑/↓ — the neighbouring rail, Enter — place, Shift+Enter — place and keep the device in your hand for the next one. If there is not enough room, the editor tells you how many modules are needed.

Bars (a distribution phase bar, N and PE) are added with a single button from a separate palette row — no dragging.

On mobile:

1. Tap "+ Add" on the right of the toolbar — the "Components" palette opens, with search and group chips (All / Favorites / Recent / groups)
2. Tap a device — the palette turns into a "Device in hand" strip
3. Tap a highlighted place on a rail. You can place several identical devices in a row; "Done" finishes
4. Or press and hold a palette row and drag the device with your finger

Devices can be dragged between rails and between positions on the same rail.

Cloning (Ctrl+drag): hold Ctrl while dragging — the device is copied with all its parameters (rating, curve, cable, consumers) into the target slot.

[screenshot: dragging a device from the palette onto a rail]

Moving devices — Smart DnD#

The drag-and-drop system in ElectroBoard automatically picks the best way to place a device depending on the situation:

Free slot → Placement#

If the target slot is free, the device simply moves there. Highlighted green.

Occupied slot → Insert with shift#

If the target slot is occupied, the system automatically inserts the device, shifting its neighbours — this works both on the same rail and when moving between rails:

• Adjacent devices shift automatically to make room
• During the drag the devices immediately show their new positions — you see the result before releasing
• A semi-transparent copy of the device being moved appears on the target slot
• If there is no room to the right, the system automatically tries to shift to the left

Cannot place → Blocked#

If there is no room for a shift, the device returns to its starting position. Highlighted red.

[screenshot: insert with shift — blue line and highlighted modules]

Selecting and configuring a device#

Click a device to select it. A properties panel appears on the right with sections (only those that apply to this device are shown):

• General — name, rating, extra parameters (characteristic, RCD type, etc.) and the room zone
• Connection — connection variant (1P/2P/3P/4P), phase, width in modules, feed direction, terminals and jumpers
• Hierarchy — the protective zone, the source (for a transfer switch/changeover — main and reserve), N input and N output, connected devices ("Feeds")
• Power source — the source role for incoming devices
• Control — the contactor for the control circuit (for contactor switches, time relays, voltage relays, multifunction relays, a smart controller)
• Input cables — the main and reserve cable (for a transfer switch and changeover)
• Load — calculated load and consumers, the "Harmonic load" (for three-phase) and "Critical circuit" marks (a load that must survive a mains outage), and "Wire to the appliance" — the length, cross-section and PE of the final wire, which feed into the short-circuit current calculation
• Cable — the device's cable (for comb members — a note that the device is fed from the comb)
• Notes — free text (collapsed by default)

At the top of the panel is the "⋯" button with the device's actions menu, and at the bottom — "Delete component". The properties panel does not close on a background click — only via the × button.

Sections can be collapsed by clicking the header. The collapsed/expanded state is remembered per device type — if you collapse "Notes" on breakers, it stays collapsed on all subsequent breakers, but does not affect other types.

Device card and actions menu#

Hover over a device — a moment later a card appears: type and name, phase and N, rating (for example "C16" or "30 mA · A"), the load in percent and amperes, the power source, and the most serious problem from the checks. Hovering over a terminal mark shows that terminal's role in words. Combs and bars have their own cards (for a bar — occupancy and source).

Right-clicking a device opens the actions menu with the same card at the top; clicking the problem row opens the checks with that device's rows highlighted. The same menu is opened by the "⋯" button in the properties panel. The actions: Properties, Duplicate (a copy on the same rail), the comb actions (Phase busbar, N-busbar, Output busbar, Add to busbar, and for a comb member — Split busbar here, Merge with busbar, Remove from busbar, Delete busbar) and Delete. An unavailable action stays in the menu with an explanation of why it cannot be performed.

On a phone, tapping a device opens a device card at the bottom with the buttons "Properties", "Actions" and "Terminals" (terminal roles in words). If the device has a problem, its row on the card opens the checks. The panel scrolls automatically so that the selected device is not hidden under the card.

Consumers#

Click "Consumers →" in the properties panel to open a drawer with the consumer list. Here you can:

• Add consumers from the catalog (29 presets across 5 categories: kitchen, bathroom, lighting, HVAC, sockets)
• Add a custom consumer with arbitrary parameters
• Change the quantity, power, cosφ, and demand factor
• See the calculated load in real time

The consumers drawer replaces the properties panel (it does not overlay it) — close it via ← or ×.

Device terminal editor#

Many devices (transfer switches, changeovers, relays, contactors, meters, RCD/RCBO, and others) let you fine-tune their terminals — the marking, placement, and internal jumpers. The editor opens in the properties panel of the selected device.

At its centre is a device replica diagram: a scaled copy of the body with terminals on their real edges (top/bottom), coloured by conductor. This is the same view as on the panel canvas — click any terminal on the diagram to open its card. Every change applies immediately (no "Apply") and syncs with the diagram and the canvas.

Terminal card#

• Terminal marking — the label per standard (IEC numbering: 1/3/5 for the primary input, 2/4/6 for the reserve, N, U/V/W for outputs — depending on the device type). You can pick a catalog value or enter your own.
• Placement — which edge the terminal sits on (Top / Bottom) and its position along the edge (a ‹ 1/8 › stepper). If the slot is occupied, the terminals swap. A hint is on the ⓘ icon.
• Input source — for dual-source devices (transfer switch/changeover) it shows which source the terminal belongs to (Primary / Reserve). The "Swap sources" button atomically swaps the whole set of primary and reserve inputs.
• ↺ in the card header resets that terminal to the default.

The device feed direction (↑ Top / ↓ Bottom) is set right here, above the diagram (for devices that support it).

Terminal role marks. Next to the terminals of every device on the canvas there are short role marks: input, output, PE, control coil, auxiliary contact, and so on. On a computer, hovering over a mark shows the label in words (for example, "Input L — primary source"). The terminal marking is taken from the part number of the real product.

Bridges & connections#

The "Bridges & connections" section (collapsed by default) manages jumpers between terminals:

• Reserve-input jumper — for multi-phase transfer switches, one toggle joins the reserve-input phase terminals into a group (for example, so a single-phase reserve feeds all phases). On the diagram and canvas it is drawn as a shared bridge bar and follows the reserve source on "Swap sources".
• Jumper list — all existing jumpers with friendly terminal labels (for example, 1 → 3) and an origin mark.
• Add manually — choose the type (Internal connection between two terminals of the same device, or a Reserve jumper), the "From"/"To" terminals, and press +. Dangerous connections (a short circuit between different conductors L↔N/PE) are blocked with an explanation.

System-managed connection types (the bond to a standalone source's neutral, a reference to a comb) are created automatically and are not offered for manual creation.

Deleting a device#

There are three ways to delete a device:

• Keyboard — select the device and press ⌨️ Delete or Backspace. Confirm the deletion in the dialog.
• Actions menu — right-click the device (or use "⋯" in the properties panel) and choose "Delete". Handy when you do not want to select the device with a separate click first.
• Properties panel — open the device settings and press the "Delete component" button at the bottom of the panel. Handy on mobile.

Warning: when you delete a device that is a parent of others (for example, an RCD with connected MCBs), the child devices lose their link to the parent.

Undo / Redo#

Any action can be undone:

• ⌨️ Ctrl+Z — undo
• ⌨️ Ctrl+Y or Ctrl+Shift+Z — redo

The ↩ ↪ buttons are also available in the toolbar. The action history is kept for the entire time you work on a project.

Protection against broken changes. The editor does not apply a change after which the panel would become inconsistent — for example, two poles of one device would get the same phase, a reference to a device or comb that does not exist would remain, a device would lose its power source, or a bar would end up fed from itself. In that case nothing changes, and a message explains the reason.

Rail management#

A panel is made of DIN rails onto which devices are mounted. Above each rail sits a quiet header: "Rail N — name", a fill bar and a counter such as "13 / 24 mod.". The rail number follows the rail's position on the panel, so after rails are deleted or added the numbering stays 1, 2, 3… with no gaps. When devices run past the end of a rail, a red "! +N" appears next to it — click it to open that rail in the Rails mode.

The maximum number of rails is 12. This matches the largest domestic and small commercial panels. For larger jobs it is recommended to split them into separate projects.

Rail name#

A name is the number (the editor computes it) plus your own suffix, such as "Incomer" or "Lighting". It is changed only in "Rails" mode: click a rail's header and the mode opens with that rail selected. Then use the "Name" field in the action panel, ✎ on the header, a double-click on the name, or F2 / Enter: only the suffix is edited (up to 40 characters), Enter saves, Esc cancels. An empty suffix leaves just "Rail N". Outside the mode the header only shows the name. On a phone the name is edited in a bottom sheet — in "Rails" mode tap "Name" in the action panel, tap ✎, or double-tap the name.

Rails mode (D)#

Rails are managed in a separate mode: press D or the "Rails" button in the tool column (on a phone — in the list of modes). In this mode the palette is hidden, devices are dimmed and cannot be dragged, and a click on a rail selects it (↑/↓ — the neighbouring rail). An action panel appears above the selected rail:

• Up / Down — moves the rail one place (Alt+↑ / Alt+↓). On a computer you can also drag the rail: while you drag, the line "Here · becomes no. N" shows the new place, and Esc cancels. Devices, combs and bus bars move with the rail, and rail numbers follow the new order. Wires you routed by hand keep their shape when both of their ends moved together; the others go back to the automatic route — the message says how many, and it has "Undo".
• Name — the suffix field
• Width — each rail has its own: chips 12 / 18 / 24 / 36, −/+ by one module (keys [ and ], with Shift — to the neighbouring standard width), and on a computer also a handle at the right end of the selected rail. Widening, and narrowing where every device still fits, moves nothing. If devices no longer fit, the editor changes nothing and asks: “Move only those that do not fit” (they go to the nearest free places on the same rail — the default), “Close gaps and shrink”, “Move them to another rail”, “Delete” or “Keep” the old width; the new edge and the devices that do not fit show in red on the board. “All” gives every rail this width in one step. On a phone the width is changed in a bottom sheet that previews the new edge on the board, with an “Apply” button.
• Arrange ▾ — "By type" (auto-sort) or "Only close the gaps" (keys S and Shift+S)
• Copy — duplicates a rail with its devices (Ctrl+D): the copy becomes the rail that follows the original, with the same width and name; the devices are copied without wires and without a feed — connect them again. When there are already 12 rails, the button is unavailable.
• Delete — an empty rail goes at once (the message offers "Undo"). For a rail with devices, the editor asks: “Move the devices and delete the rail” — the devices take the free places on the rail you pick in the list, in the same order, a comb moves whole, and rails without enough room are unavailable in that list; or “Delete along with the devices” (Ctrl+Z brings everything back). The last rail can be deleted too (Delete key).

Below the last rail there is a "New rail · becomes N-th" button (key A); the new rail takes the width of the one above it. The mode bar at the top shows the number of rails and the occupied modules and changes the spacing between rails (−/+ in 0.5 cm steps). Leave the mode with "Done", D or Esc (when a rail is selected, the first Esc only clears the selection).

When no rails are left on the panel, the canvas shows a card with a width choice (12 / 18 / 24 / 36 mod.) and an "Add the first rail" button.

Auto-sort ("By type")#

"By type" orders the devices on a rail in a logical sequence:

1. Incoming devices (isolators, meters)
2. RCDs and RCBOs (protective devices)
3. Circuit breakers
4. Auxiliary devices

Within each type — sorting by phase (L1 → L2 → L3) and by rating (from higher to lower). A parent device is always placed before its children. The action supports Undo (Ctrl+Z).

Bars#

At the bottom of the panel the bars are shown — N (neutral), PE (protective earth), and PEN (combined). The set of bars is determined automatically depending on the chosen earthing system:

• TN-S — separate N and PE bars
• TN-C-S — N, PE, and PEN bars
• TN-C — PEN only
• TT — separate N and PE
• IT — PE only

When an RCD is present, a separate N bar is created automatically for each protection group. RCBOs, voltage relays, and other devices with an N pole connect to the panel's common N bar.

Feed of N and PEN bars#

Neutral bars (N and PEN) always show where they are fed from: the bar panel has a chip with the source. If the source is not set or is not determined unambiguously, the chip names the reason (for example, "No source chosen") and offers a one-click "Confirm: …" option; a source set automatically carries a "please check" note. If devices with an undetermined neutral depend on the bar, the panel offers "Connect to this busbar" as a single step.

If deleting a rail or changing its width would break the feed of a bar, the editor does not do it silently but offers "Disconnect the bus and continue".

Bar rating. The bar panel has a "Bus rated current (A)" field with a quick pick (63, 80, 100, 160 A, "custom" or "no rating"). An empty field means the rating is not declared: the app substitutes nothing, and the overload check is not run for the bar — a separate warning says so.

Phase distribution bars (L1/L2/L3)#

Besides N/PE/PEN, the "Distribution bars" palette has a "+ L" button — it adds a phase distribution bar to aggregate a group of 1P/3P breakers on one phase. It works for all panels (1-ph/2-ph/3-ph) — even on a single-phase panel, 5+ breakers on L1 benefit from a shared L bar instead of a "web" of wires.

Owner-bound model: after adding a bar, you choose its owner in its properties (a parent distributor, for example the incoming MCB or a contactor) and the phase. The bar colour is derived automatically from the phase. Until an owner is assigned, the bar is shown as a grey placeholder with an "L" badge.

Connecting children: for a 1P/3P breaker, the L1/L2/L3 bars appear as options in the "SOURCE" dropdown in the properties, alongside the parent breakers. When you choose a bar of a different phase for a 1P breaker, the phase switches automatically.

Phase combs: a 1P comb can be fed directly from an L bar — one wire from the bar to the comb instead of separate wires to each member.

Mounting zones#

Bars can be placed in different zones of the panel:

• Bottom zone — the standard position under the rails (horizontal)
• Top zone — above the rails (horizontal)
• Left / right side — vertical strips on the side of the panel
• On a DIN rail — mounted on any rail as a modular device

The mounting zone can be changed in the bar's properties panel, or you can drag the bar between zones. The same panel has an "Insulation" field: on a DIN rail a bar can be "Bare" or "Insulated", and off the rail the choice is locked — bare only.

Terminals and assignment#

Each bar has a defined terminal count (standard sizes: 2, 4, 6, 8, 10, 12, 15, 18, 24). The system automatically:

• Counts the occupied terminals — based on the connected devices
• Offers to increase — if there are more connections than terminals, a dialog appears offering the nearest standard size
• Assigns terminals — automatic distribution (the "Auto" button in the properties panel)

The properties panel shows the bar's terminal-assignment list. Clicking a row highlights the corresponding module on the panel with a pulsing animation.

Comb aggregation in the connection list#

An N comb fed from this bar is shown in the list as a single group terminal instead of N separate rows for each comb member. This is physically correct: one wire runs from the bar to the comb, and the comb itself then distributes N to its breakers.

• A chevron arrow ▶/▼ on the comb row — expands/collapses the list of internal devices
• An "X dev." badge — the number of comb members
• Nested members — read-only, managed via the comb panel (a "comb" badge on each row)

The occupied-terminal counter and auto-assignment count by groups: a comb of 5 breakers = 1 occupied terminal, not 5. This fixes the case where a 10-terminal bar falsely showed "overflow" due to a small number of physical connections.

"N incomer" — a virtual row from the mains#

When the panel's root device (with no parent) has no N pole (a 3P MCB, generator, inverter, UPS without N), a virtual row #1 "N incomer (mains/source)" is added to the bar's terminal list — the physical N cable arrives at the bar directly from the mains, outside the breaker. If the root has an N pole (for example a 4P MCB or a 3P+N SPD as root), this row is not needed — the root is itself the source and is shown as an ordinary connection.

Highlight when a bar is selected#

When you click a bar, the related devices are highlighted:

• Blue dashes — devices with a direct connection to the bar
• Yellow dashes — indirect descendants (supply passes through the bar, but without a direct wire)

More: Network settings

Combs (busbar combs)#

A comb is a copper connecting bar that replaces the individual wires for a group of breakers. Instead of a "web" of wires from a parent to each child device — one compact bar.

Creating a comb#

A right-click on a breaker opens the actions menu (the menu calls a comb a "busbar"):

• Phase busbar 1P (the number of devices next to it) — an input comb that replaces the wires from the parent to the group
• Output busbar 1P (the number of groups next to it) — replaces the wires from the breaker to its child devices

The comb type (1P, 3P, 1P+N, 3P+N) is determined automatically from the breakers' phases.

Comb types#

Type	Conductors	Purpose
1P	L1	Single-phase groups
3P	L1, L2, L3	Three-phase groups
1P+N	L1, N	Single-phase with neutral
3P+N	L1, L2, L3, N	Three-phase with neutral
N	N	Neutral distribution (N comb)

N combs — a separate DIN comb for the N conductor instead of individual wires to each breaker. They are fed directly from an N bar, cascaded from another N comb, or from a distributor device — for example a 4P cross-module, which is itself a point of N distribution. The latter is useful when the panel has no N bar yet and you want to quickly create an N comb under the cross-module. The breaker's context menu offers a "From N bar / From cross-module" sub-menu when both options are available.

Phase selection for single-phase combs#

When a comb of type 1P or 1P+N is fed from a three-phase parent (3P/3P+N), a "Phase" selector appears in the properties panel — L1, L2, or L3. This lets you explicitly set which phase the comb is on, without editing each member separately.

Phase propagation (BFS): when you change the phase of a parent 1P/1P+N device, the system automatically updates the phase of the corresponding comb, of all single-phase child devices, and of the comb members in the subtree. Three-phase parents (3P/3P+N) do not propagate the phase — each child chooses on its own. 2P descendants are not affected.

Locked fields on comb members#

Members of an input comb have locked fields in the properties panel: the source, the phase, and their own N bar — the comb sets them. These parameters can be managed only via the comb panel — this prevents state inconsistency. The locked fields show a "managed by comb" badge. Devices fed by an output comb do not lock their own fields.

When you change the comb feeder (via the comb panel), all members are automatically reassigned to the new parent.

Phase cascade#

Phase combs automatically lay out a skip pattern — they skip slots between breakers of different phases. For example, in a mixed 1P/3P group: 1P on L2 + 3P (L1L2L3) + 1P on L3 — the comb correctly connects only the matching phase of each breaker, without shorting the neighbours.

The comb is drawn to the real dimensions from the catalogues — one moulded body above the modules with no gaps, with coloured phase rings and the rating on the body. A comb under the devices is a mirror image of the upper one. A comb with no power assigned is marked with a yellow "?". A wire that crosses a comb is visible on top of it.

Feeding from another rail#

A comb on one rail can be fed from a breaker on another rail (or from an N bar separately from the comb). The feeder breaker and the comb do not have to be on the same rail.

N cascade (comb from comb)#

An N comb can be fed not only from an N bar but also from another N comb — a cross-rail cascade, to reduce the number of wires on the board.

Input and output#

A breaker can have two combs at once on different sides:

• Input (top) — replaces the wires from the parent device
• Output (bottom) — replaces the wires to the child devices

Properties panel#

Clicking a comb's body selects it and opens a panel on the right:

• Label — an arbitrary name (for example, "Lighting group")
• Role — input or output
• Conductors — which phases the comb carries
• Inc — the comb's rated withstand (validated against the total load)
• Membership — add / remove a breaker from the comb, a subset filter (show only members)
• Split / Merge — split a large comb into smaller ones or merge adjacent ones
• Part number — the manufacturer number for the bill of materials
• Delete — restores the individual wires

Context menu#

A right-click on a breaker opens the actions menu (see "Device card and actions menu"), where the comb actions are collected:

• Phase busbar, N-busbar, Output busbar — create a new comb
• Add to busbar — if the breaker is next to an existing one
• Split busbar here — divide into smaller groups
• Merge with busbar — if a compatible comb with the same conductors and feed direction is adjacent
• Remove from busbar / Delete busbar

Automatic comb adaptation#

When a breaker's parameters change, the comb adapts automatically:

• Flipping (a feed-direction change) — the breaker is removed from an incompatible comb
• A connection change (1P → 3P) — compatibility is checked; on a mismatch the breaker leaves the comb
• Moving to another rail — automatic removal from the comb
• Changing the parent to an incompatible one — the breaker is evicted from the comb
• On each such action a toast message appears at the bottom of the screen with navigation to the cause

Validation rules#

A comb requires:

• At least 2 breakers
• All on the same DIN rail
• A common parent device
• Identical conductors (phases)
• The same feed direction
• No overlap with other combs on the same side

Validation indicator#

A checks strip runs under the toolbar, above the canvas:

• 🔴/🟡/🔵 counters — the number of safety errors, issues and recommendations. A click on the strip expands the list of checks over the canvas; you can change the list height by dragging its bottom edge, and the open state is remembered
• 🟢 All good — there are no issues, and the strip is not clickable
• Checks unavailable — for a panel saved by a newer version of the app: the checks are switched off, and a click on the strip explains why

Next to it is a chip of the active check regime (for example, "IEC 60364"): a click opens the panel settings in the "Validation" section. In the list the checks are grouped: Safety, Issues, Recommendations. A row carries "✓ Fix" if an auto-fix exists, "→ Go to" the device, or "⚙ Settings"; a click on a row expands the details and the link to the norm.

On a phone, under the toolbar there is a button with the counters (or "All good"); it opens the bottom "Checks" panel with the same list.

Tool column#

To the left of the canvas is a vertical tool column. At the top are the palette button (hide/show, *Ctrl+*) and the "Potentials" panel button (L). Below them are the cursor modes, each with its own key (the keys also work in a non-Latin keyboard layout):

Key	Mode	What it does
V	Select	Pick a device or wire, drag it, open its properties (the default)
H	Hand	Pan the canvas by dragging without touching devices (holding Space is a temporary hand)
W	Wiring Mode	Dims devices and rails, leaves the wires (also Alt+W)
P	Probe	Continuity check of potentials
N	Numbering	Node numbers on the canvas
R	Ruler	Distance measurement
D	Rails	Rail management (see "Rails mode (D)")

After a mode change a hint with the tool name appears on the canvas for a few seconds. Esc steps back one step at a time: it puts a device "from your hand" back, clears the measurement and isolation, clears the rail selection, and then returns the "Select" mode. On a phone the modes are chosen with the mode button in the toolbar — it opens the "Tools" sheet.

"Potentials" panel#

The panel is opened by the "Potentials" button (L) and gathers the canvas filters and the list of the panel's potentials:

• Classes — the phase filter "All / L1 / L2 / L3" (phases appear only on a three-phase panel) and the N and PE toggles, which hide or show the corresponding bars and wires
• Sources — a filter by power source (if the panel has several sources): it shows the loads of one supplier, the rest fade; devices behind an ATS are shown with a "via …" caption
• List of potentials — grouped by L1/L2/L3/N/PE: the mark (for example, L1-1), where from and where to, the bars and the wire count. A click on a row isolates that potential on the canvas, a second click clears the isolation; ↑/↓ — the previous/next one

When the panel is closed and some filter is on, a "Shown: …" pill is visible on the canvas — a click opens the panel, "×" resets all the filters. On a phone the panel opens with a separate "Potentials" button in the toolbar and takes the lower half of the screen.

Probe and numbering#

Probe (P) — click a wire, and its whole potential lights up (all wires and terminals connected to it). The second point is a continuity check: the editor tells you whether it is one potential or different ones. A switching device counts as a potential boundary even when closed (as drawn). A control-circuit wire is not part of the power potentials (L, N, PE). Entering the mode opens the "Potentials" panel.

Numbering (N) — shows node numbers on the canvas (L1-2, N-3…), as on a wiring diagram. A click on a number isolates that potential.

Ruler#

Ruler (R) — drag from point to point, and the editor shows the distance in millimetres and modules, as well as Δx/Δy. The ruler snaps to wire and rail ends; Shift — horizontal or vertical only, Alt — no snapping. Vertical distances are counted by the rail pitch.

Wire Mode#

Wire Mode is a special visualization mode that shows all conductors on the panel. Toggle it with the W key or ⌨️ Alt+W, or the "Wiring Mode" button in the tool column (on a phone — in the "Tools" sheet).

The phase filters and N and PE are now in the "Potentials" panel — use them to hide the corresponding conductors and check specific circuits.

The state of the display settings (diamond visibility, tag mode) is preserved across wire-mode toggles — no need to re-enable it every time.

In wire mode, clicking a bar or a comb opens its properties panel; a click on empty space closes any panel and clears the selection.

The "Wiring editor" panel (on the right) contains sections in order of how often they are used:

• Display — two main toggles:
  • All diamonds — show/hide the edit points on all wires at once
  • Wire tags — labelling modes with a hint of the active mode: Off / Wires (a running number W001) / Terminals (the address of the opposite terminal QF1:2) / Nodes (one potential = one number L1-1, as on a wiring diagram). In "Nodes" mode, clicking a wire highlights the entire equipotential node (all terminals at the same potential); there is a separate "Probe" tool for continuity checks
• Selected wire / Selected — information about the selected wire (phase, route, from→to) or the selected group, with buttons to reset the correction and clear the selection
• Manual corrections — a collapsible list of all wires with a manual route correction. Each item shows a coloured dot, the phase, and from→to. A click selects the wire on the canvas; the ↺ button resets an individual correction
• Cables — an overview of all cables on the panel (devices, combs and bars) with status badges (✓ Auto / ⚠ Undersized / ✎ Manual / Not sized — with the reason), a filter (All / Auto / Undersized / Manual / Not sized), the button "Accept recommendations (N)" for undersized cables and "Switch device cables to auto" (the feeders of combs and bars are not changed). Clicking a row opens an inline editor (one at a time) with the wires highlighted on the canvas; Esc collapses it. Details — in Cable system
• Colour standard — a palette choice (IEC, legacy, NEC, ElectroBoard Classic) in a compact 2×2 grid
• Wire thickness — 5 presets (thin → thick) for the visual line thickness on the canvas. Handy for printing panels with many circuits, where thin lines overlap
• Wire lengths — a length calculator based on the real geometry of the routes. It shows a breakdown by phase (L1/L2/L3/N/PE) with the wire count and length of each. It supports an installation margin (+10/15/20%). Clicking a phase expands the individual wires with their lengths
• Rail spacing — a slider from 10 to 50 cm that scales the SVG display of the physical distance between DIN rails
• Hints — a collapsible accordion with keyboard shortcuts and tips

To change a wire's route, drag the diamonds (◆) on the conductors: a horizontal diamond — up/down, a vertical one (↔) — left/right.

Selecting and labelling wires#

• Clicking a wire — selects it (it is highlighted brighter, the rest dim). Next to each connection a marking is shown (for example, W001/A3:2)
• Clicking again on a selected wire — resets its manual route to the automatic one
• Shift+Click — adds/removes a wire from the selection group. Resetting the manual route applies to the whole group at once
• Tab / Shift+Tab — moves the focus between wires with an automatic scroll to the chosen one

Undo/Redo of routes#

Manual route changes (dragging the diamonds) support Ctrl+Z / Ctrl+Y — just like adding and deleting devices.

[screenshot: Wire Mode with the wiring-editor panel]

Minimap#

When you zoom into large panels (3+ rails), a minimap appears in the bottom-right corner — a thumbnail of the whole panel with a rectangle for the currently visible region.

• A click on the minimap — instantly moves the view to the chosen point
• Dragging — smooth navigation around the panel
• Resizing — drag the minimap edge for a convenient size (S/M/L/XL)
• The minimap hides automatically when the whole panel is visible on screen

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Toolbar — in detail#

On a computer the toolbar is a single row, from left to right: the project pill, ↩ Undo and ↪ Redo, the Iₖ (fault currents) and Co (diversity factor) toggles, the input-load chip, "Share", "Export ▾" (PDF panel / Labels / EPS diagram) and "⋯" — the app menu. In a narrow window some buttons show only icons, and "Co" hides in a separate "⋯" menu. On mobile the toolbar is two rows (see "Mobile interface").

Panel settings, wiring mode and filters are not in the toolbar: the settings are in the right panel when nothing is selected (see "Panel settings"), wiring mode is in the tool column, the filters are in the "Potentials" panel. The AI-consultant and ticket buttons are at the right edge of the canvas.

The language of the buttons#

The toolbar has a simple grammar. Once you know it, you can read any button, even an unfamiliar one:

• No frame means an action: you press it, it happens, it is done. Undo ↩ and Redo ↪ are actions. They fade when there is nothing to do.
• A frame means a toggle: it holds a state. Iₖ and Co are toggles. An active toggle is tinted in its own colour.
• A vertical rule separates the actions from the toggles.

Every button explains itself: hover for a tooltip on the desktop, or press and hold on a touch screen to reveal its name.

Save indicator#

In the project pill, next to the project name, there is a coloured dot (the tooltip says what it means):

• 🟢 Green — all changes are saved
• 🟡 Yellow — saving...
• 🔴 Red — a save error or no connection (the changes are saved locally and will sync when the connection is restored)

Incomer loading#

The load chip shows the ratio of the total load to the allocated power:

• Up to 70% — normal operation
• 70–90% — caution, approaching the limit
• Over 90% — overload

A dot appears beside it only when the checks have found something worth your attention. On a clean board there is no dot at all.

Phase balance#

On a wide screen the per-phase breakdown is visible right in the toolbar; on a narrower one, clicking (or tapping) the load chip opens the full breakdown:

• Incomer — total power and current.
• Per phase — for L1, L2 and L3, current first; a click on the units switches A / kVA (the choice is remembered).
• Phase balance — how evenly the load is spread. It shows the imbalance as a percentage and names the most heavily loaded phase. When the imbalance is too large, a hint suggests which phase to move some loads away from.
• Go to checks — jumps to the list of findings.

The imbalance thresholds come from the board's check regime (see "Board settings"), so they agree with what the Validation panel reports. On a single-phase board the balance section is not shown at all.

Fault currents (Iₖ)#

The Iₖ button opens the "Fault currents" panel in the right panel (on a phone — a bottom sheet). At the top is the panel summary: "Safe", "Conditionally safe" or "Needs attention", with the number of problems, warnings and provisionally-OK devices. Below, the devices are grouped:

• Problems — full cards: for each axis — Disconnection (Zs) (will the protection trip within the required time) and Capacity (Icu) (will the device withstand the fault current), a plain-language explanation and hints on what to do (for example, declare the actual source or measure the loop impedance)
• Warnings — each device takes one summary row, with the details expanding on a click; on the right is an action ("Connect device →", "Set length →", "Fix length →" or "Go to device →")
• Provisionally OK — a collapsed section with the devices that pass; expanded by default only when there are no problems and no warnings

Below the list is the "Busbars and combs" section (if there are findings for them). Numbers with real limits are shown in the evidence lines, for example Zs 2.10 Ω > 1.53 Ω; hover (or press and hold) over Zs, Ik, Ia or Icu to see what it means.

If the fault source has not been declared, the panel warns that it is calculating from typical network values and offers "Specify fault source →" — figures marked with an asterisk * are assumed defaults.

App menu (⋯)#

The far-right toolbar button "⋯" (on a phone — ≡) opens the app menu:

• Install — install ElectroBoard as an app (only when the browser offers it)
• Theme — a click on the row switches between the light and dark theme
• Language — choose the interface language (a list with a flag and the native name of the language)
• Support project
• Documentation — opens this documentation in the interface language in a new tab
• Home — return to the site's home page (if there are unsaved offline changes, the editor asks for confirmation)

On a phone the same menu also contains Export (PDF panel / Labels / EPS diagram) and "Panel settings".

Status bar#

At the bottom of the editor on a computer is the status bar: the standard mark, the occupancy of each rail in modules, a hotkey hint and the app version (for example, "v2.0.0 beta") — a click on it opens the changelog. On a phone the status bar is not shown.

Mobile interface#

On a mobile device the interface is adapted:

• The toolbar — two rows. The top one: the project pill (name + save dot; a tap opens the "Project" sheet with the name field, "Rename", "My projects" and the .eboard file), Share, the app menu ≡. The bottom one: the tool rail.
• The tool rail scrolls sideways: ↩ ↪, the mode button (shows the icon of the current mode and opens the "Tools" sheet with all the modes), Iₖ, Potentials, Co. Its right edge carries a gradient and a "›" chevron — a hint that more buttons follow.
• The pinned cluster on the right does not scroll: the load chip and + Add. In wiring mode they swap to ⚙ Wiring and Done, and in "Rails" mode — to Done.
• Checks — the button with the counters under the toolbar opens the bottom "Checks" panel
• The palette — the bottom sheet "Components" with search and group chips; a tap on a device takes it "into your hand" (see "Adding devices")
• The device card — a tap on a device opens a card at the bottom with the buttons "Properties", "Actions", "Terminals" (see "Device card and actions menu")
• The properties panel — a bottom sheet (dynamic height: 40vh by default, up to 85vh when expanded)
• The wiring panel, the fault-current panel and the panel settings — also bottom sheets, with the same gestures
• The "Potentials" panel — takes the lower half of the screen and does not cover the panel completely
• The consumers drawer — replaces the properties panel in the same bottom sheet
• The project list — a full-screen overlay
• Dragging — press and hold a device or a palette row and drag it with your finger
• The AI and ticket buttons hide automatically when a device is selected or any bottom sheet is open — so they do not cover the panel
• The status bar (hotkeys, rails, version) is hidden on mobile

Bottom sheet — gestures#

All bottom-sheet panels (palette, properties, actions, comb, bar, consumers, wiring, fault currents, checks, panel settings) support the same set of gestures:

• A drag handle (a horizontal bar at the top) — drag to change the height
• Snap zones — on release the panel automatically snaps to one of the positions:
  • ≤14vh — the panel closes
  • 14–60vh — returns to the default (40vh)

  • 60vh — expands to the maximum (85vh for properties, 75vh for the comb/bar)

• Swipe down to close — drag down to 14vh to close
• Backdrop click — a click on the dimmed background also closes the panel
• Keyboard-aware — when a virtual keyboard opens (e.g. in the palette search field), the panel automatically rises above it via the visualViewport API

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Interface theme#

ElectroBoard supports two themes:

• 🌙 Dark — the default, optimized for long work sessions
• ☀️ Light — the Windows 11 default, comfortable in bright office lighting

The theme switch is in the app menu ("⋯", on a phone ≡) → the "Theme" row. The state is saved between sessions.

Details:

• The toolbar chrome (the top bar with buttons) is dark in both themes. This is a design decision after the pattern of professional CAD tools (Photoshop, Figma, Fusion 360): a contrasting bar of controls visually separates the working canvas from the UI
• The canvas is light in both themes (like a sheet of paper — a CAD convention)
• The palette, sidebar, and dialogs adapt to the theme
• The phase colours (L1/L2/L3/N) are invariant per the IEC 60445 standard
• The power-source roles have invariant colours (mains = blue, generator = amber, inverter = purple, and so on)

By default the system theme is used. On the first click, the switch locks to the chosen option.

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Project pill#

At the left of the toolbar is a single control: logo + project name + save dot + ▾. It is the single entry point to everything that concerns the project. A click opens a menu (on mobile — the "Project" sheet with the name field):

• My projects — switch to another panel (also Ctrl+O)
• Rename — the name turns into an input field; Enter confirms, Esc cancels. The quick key is F2
• Save .eboard / Open .eboard — the project file

Neither a single nor a double click on the name starts renaming — only "Rename" or F2 does.

Switching between projects#

Press ⌨️ Ctrl+O or choose "My projects" in the project pill to open the project list. Here you can:

• Move to another project
• Create a new project
• Delete a project (with confirmation)

💡 Auto-name: if you leave the name field empty when creating a new project, a name is generated automatically — "New panel", "New panel (2)", "New panel (3)", and so on (the first free number is used). Handy when you need to quickly create a panel for a test or sketch.

Panel settings (⚙)#

On a computer the panel settings are the right panel in its "nothing selected" state: click an empty spot on the canvas, and "Panel settings" appears on the right. The panel can be collapsed into a narrow strip with the "Collapse panel" button and expanded back. On a phone the settings open from the app menu ≡ → "Panel settings". The check-regime chip and the "Specify fault source →" hint lead here too.

The parameters are grouped into sections:

• Network — Preset (a typical configuration; "Custom" if you changed the parameters), Phases (1-ph / 3-ph; 2-ph when the regime allows it or the panel is already two-phase), Voltage, Earthing (TN-C-S / TN-S / TN-C / TT / IT), PEN section (in the panel or at the input — for TN-C-S), Frequency; below them — the phase and line voltage
• Validation — the "Regime" row: Ukraine (Ukrainian national standards) or IEC (IEC 60364). The regime determines which norms the panel is checked against and which documents the warnings refer to. Until a regime is chosen explicitly, it is assumed from the interface language — a note says so; click the regime you need to confirm it. If a regime change would hide some warnings, the editor first says how many and asks for confirmation
• Power — the allocated power in kW or A (for the incomer-overload check)
• Routing — the ambient temperature and "Circuits in bundle" (1–50) for the ampacity correction factor
• Fault source — unknown / measured Ze / fault current at the input / transformer (see Automatic Checks)

The "Power", "Routing" and "Fault source" sections are collapsed while nothing is set in them; when collapsed, the header shows a summary (for example, "15 kW · 25 A" or "— not set").

Visual indicators on devices#

• Source-role icon: above the body of a device with a source role (inverter, solar, generator, battery, UPS), an emoji role icon is shown. It lets you visually tell a supply entry point from ordinary devices. For a mains source and "other", no icon is drawn.
• 2P mode badge: for an MCB/fuse/contactor/time relay/isolator in the 2P variant, the phase badges in the body match the pole configuration exactly: L+N mode → one L badge (N is not shown as a phase), L1+L2 mode → two badges, L1 and L2.