What's new

Every fix and change to PickettPanel, newest first. If something behaves in a way a real panel wouldn't, report it and it'll show up here once it's fixed.

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  1. 1.1.4

    Current version

    50 projects to build and fault-find, with hidden faults on Easy or Hard — plus motors that turn, timers with a COM terminal, drives with real 24V inputs, logic on the custom PCB, side panels you can hide, and fixes for timers, transformers and drawings.

    New

    • 50 Projects: a series of control circuits to build and fault-find, from a two-hand control to a PLC mixing tank, with five big Challenge projects at the end, three of them over 40 parts. Open any project working, or pick Easy (one hidden fault) or Hard (three, on different parts) — the faults are different every time. Open it from Presets → 50 Projects & fault finding.
    • Fault-finding panel. An Easy or Hard project opens with a panel: operate the circuit, use the meter, then press Check answer and click the part or wire you think has failed. On Hard you have to find every fault, the way you would on a real job; each one you find is replaced, so the symptoms can change as you go. Reveal shows the answer, and Share this fault sends the same circuit and faults to someone else.
    • Projects you’ve fault-found are ticked on the 50 Projects page, with a count of how many you’ve done.
    • More faults to inject. Timers can have an open coil, a contact stuck at rest or a welded contact. Breakers can have their contacts open, fail to trip (so the protection upstream has to clear the fault), or lose one pole of a 3-pole MCB and single-phase a motor. A Load can be partly shorted (trips after a while) or shorted (trips straight away). Two wiring mistakes can be injected too: NO and NC wires swapped on a pushbutton, contact or timer (T1 and T2 on a 3-position selector), and two phases swapped on a motor, so it runs the wrong way. A wire can have a loose connection that drops out every few seconds, and an overload can have its 95-96 trip contact open without tripping, or be set too low so it trips after the motor has run for a while. The Easy and Hard faults in 25 of the 50 Projects now include them.
    • Current flow on / off. Tools → Current Flow hides the glow and the moving dashes on live wires, so the canvas doesn’t give the fault away: find the live wires with the meter, as you would on a real panel. Lamps, coils and motors still show what they’re doing, and your choice is remembered. Hard projects always run with it off, until you’ve found every fault or pressed Reveal.
    • Settings at a glance. The Circuit Status panel now shows what’s on or off: current flow, faults shown, the meter, wire numbers and the drawing symbols. Click a line to change it.
    • Motors turn. While you simulate, a running motor’s shaft spins: it runs up when started, follows the drive’s speed, and coasts down when it’s switched off, in the direction its arrow shows.
    • Timers have a COM terminal. TON and TOF timers now have a changeover contact like a real timing relay: wire your supply to COM, and COM–NC is closed at rest while COM–NO closes when the timer operates. As on a real timer, the contact needs a supply on COM: every preset and project has COM wired, and a circuit saved earlier with nothing on COM tells you when it opens.
    • Drives have a +24V terminal. A drive’s control inputs (DI1–DI3) are 24V DC, as on a real drive. Feed your buttons from the drive’s own +24V terminal; COM is its 0V, or the place to connect an external 24V supply’s 0V. The VFD and PLC + VFD presets and projects 37 and 38 are wired this way.
    • Logic on the custom PCB. Give each output a rule: AND, OR, XOR, NAND, NOR and NOT, an on-delay (AFTER 3), or compare an input’s voltage with > < >= <= == — for example LOW = SUPPLY < 200 AFTER 2. The block now looks like a circuit board, with tracks to its terminals.
    • PLC editor light mode: the ☀ button in the ladder editor switches to a white sheet with dark ink, keeping the grid. It’s remembered on your device.
    • Hide or resize the side panels: the tab on each panel’s edge hides it, and dragging the edge resizes it. Your layout is remembered.
    • Launch tips: a short tip each time you open PickettPanel. Switch them off from the tip itself.
    • Drawing colours: PDF drawings are now black by default, as professional drawings are. Pick Colour in the export window to keep the training colours; your choice is remembered.

    Improved

    • Works by touch on tablets. Press and hold START, RESET or any push button with your finger and it stays pressed until you let go, the same as with a mouse. Drag empty space to move around the drawing, pinch to zoom, and tap a part in the parts panel to add it. On a phone, PickettPanel now says it’s made for a bigger screen and offers to send you the link, or you can try it anyway with the side panels hidden.
    • Protection is always on. A short circuit now always trips the fuse or breaker in its path, and only that one: of the devices the short flows through, the lowest-rated operates first. With no fuse or breaker in the path, the supply’s own breaker trips. Strict Mode has gone from the Tools menu, because it’s now how every circuit behaves.
    • Mains on a drive input trips the drive. Put 230V on DI1–DI3 and the drive faults with FLT DI and explains why: on a real drive it would destroy the input card. A circuit saved before this version that feeds a drive’s inputs from the mains supply tells you so when it opens: move those wires to the drive’s +24V.
    • Wires line up. The 3-phase supply, 3-pole MCB, overload, motor and drive now all space their phase terminals the same distance apart, so parts placed in line wire up dead straight.
    • Help → Parts Guide: what every part in the left-hand panel does, its terminals and how to set it up — starting with how to make a contactor or relay from a coil and its linked contacts.
    • Meter on / off. The DM-10 has a ⏻ button: switch it off and the leads stay clipped on while you wire and edit as normal, then switch it back on to read. No more closing and reopening it.
    • The 3-pole MCB, 3-position selector, control transformer and motor now change to IEC or ANSI symbols with everything else.
    • The drawing uses your tags. A part you’ve tagged (QF1, KM1, FU1, OL1, KT1…) keeps that tag on the PDF drawing, so it matches the canvas; it used to be renumbered (QF1 became Q1, OL1 became F2). Devices are numbered as you drop them (KM1, KM2, QF1…), and parts with a name instead of a tag (START, RUN) still get a designator on the drawing.
    • A contactor’s contacts only link to a contactor, and a relay’s contacts only to a relay. Validate Circuit flags an older circuit that mixes them.
    • The single-pole breaker is now called an MCB, like the 3-pole one.
    • Drawings leave nothing out silently. Loads wired in series are drawn on one rung, a circuit fed from a control transformer gets its own sheet with X1 / X2 as the rails, a feed taken from a coil’s A1 through a contact is drawn, and anything that still can’t be drawn (like contacts straight from L1 to N) is listed under Drawing notes.
    • Easier to select wires. A click right on a wire picks it, even where it runs beside a part; where wires share a line, click again for the next one. Clicking a selected wire no longer leaves a stray bend.
    • Contactor terminal markings. Main poles show 1/L1–2/T1, 3/L2–4/T2, 5/L3–6/T3, as printed on a real contactor, and contacts show their numbers (13–14, 21–22…) on the canvas as well as on the drawing. A contact becomes a main pole once it’s wired into the power circuit, or double-click it and type 1, 2 or 3 to set it yourself.
    • A small, faint PickettPanel mark sits in the bottom-left corner of the canvas (behind your circuit), and PDF drawings say “Drawn with PickettPanel” in the title block. Circuits and drawings you make are still yours.
    • To link a contact to a coil, double-click the contact and type the coil’s name (KM1, K2…), instead of its internal ID.
    • Help → Drives & Motors explains the drive’s 24V inputs, +24V and COM, and the new FLT DI fault code.
    • The fault-finding challenges now live in the 50 Projects: the 14 challenges are the Guided option on their six circuits (Start/Stop, Indicators, On-Delay Timer, DOL, Forward / Reverse and VFD). Challenge links you’ve shared still work, and your progress carries over. The Challenges button has gone from the top bar.
    • The Presets menu now lists the 10 core circuits; the rest are in the 50 Projects. Circuits you’ve saved and links you’ve shared still open as before.
    • Help → Fault Finding now explains the 50 Projects: Easy, Hard and Guided, and how the fault-finding panel works.
    • In the PLC window, inputs are on the left and outputs on the right, like a real I/O layout.
    • A circuit that contains parts this version doesn’t have now opens with those parts left out, and tells you so, instead of failing to load.

    Fixed

    • Off-delay timers no longer switch on by themselves. An off-delay timer that had never been energised turned its output on as soon as you started simulating, so a stair light or a fan run-on started on. Its output now only comes on once the timer has been energised.
    • An off-delay timer’s NC contact now works. Wired from COM, it’s closed at rest, opens as soon as the timer is energised, and closes again once the off-delay has run out.
    • Loads fed from a control transformer whose secondary is earthed (X2 linked to PE) now work. Earthing the secondary used to cut them off.
    • A relay or lamp switched by a timer that is itself driven from another timer’s output now switches when it should.
    • Single-phase PDF drawings now show the return as N, never PE, and a circuit fed from a 3-phase supply is labelled L1 230V and N.

  2. 1.1.3

    A big one: a new DM-10 multimeter, VFD speed control, seven new presets, a 3-pole MCB, four new fault-finding challenges, drives that trip on output faults — and a long list of fixes, many from your feedback.

    New

    • Build your first circuit: a step-by-step guide that walks you through wiring a push button and a pilot light, then simulating it. It checks your circuit as you go, so you can do each step your own way. Start it from the top of the Presets menu, or from Help → Getting Started.
    • DM-10 multimeter: a new meter with a rotary dial — V~, V⎓, A and Ω. On A it goes in series: open the circuit, put the leads either side of the gap and read the current (put it across a supply and its fuse blows, like a real one). Ohms is a dead test: it reads Err on a live circuit and O.L on an open one. Open it from Tools → DM-10 Multimeter.
    • VFD speed control: click the drive while it’s running and drag the slider from 0 to 50 Hz — the drive ramps to the new speed, and its display shows the actual Hz with a marker at the setpoint. You can also set it in Edit mode, and it’s kept in saves and share links.
    • Motor current follows the load: click a motor to choose its load. A Conveyor (constant torque) draws about full-load current at any speed; a Fan / pump draws less as it slows, down to its magnetising current (about a third of FLC). The drive’s supply current falls with speed either way, because it follows the power. Measure both with the DM-10 on A — Help → Drives & Motors explains it.
    • 3-Pole MCB: a circuit breaker that switches and protects all three phases together (poles 1-2, 3-4, 5-6). The DOL, Forward / Reverse and VFD presets now use one as QF1, so switching it off isolates the whole motor circuit — and it shows across all three phases in the PDF power circuit.
    • Seven new presets: Two-Location Control (start and stop from two stations — STOPs in series, STARTs in parallel), Timed Sequence Start (conveyor 2 starts a set time after conveyor 1, and can never run without it), PLC + VFD (a PLC gives the drive its run command and reads back its running and fault signals, while E-STOP and STOP are hardwired to the drive), Jog / Run (a selector breaks the seal-in so the motor only runs while START is held), Hand-Off-Auto (a pump on a 3-position selector: HAND runs it, AUTO hands it to a level switch), Fan Run-On (an off-delay timer keeps the fan running for 10 seconds after the heater switches off) and E-Stop & Reset (releasing the E-STOP doesn’t restart anything until someone presses RESET).
    • The Presets and Tools menus now scroll on smaller screens, so nothing is cut off at the bottom.
    • Presets are now laid out with proper spacing on every screen size — parts no longer end up on top of each other on a smaller screen — and the view zooms out to fit the whole circuit when it wouldn’t otherwise fit.
    • Four new fault-finding challenges, three of them Hard: a reversing starter that only runs forward, one whose interlock has failed and slams the motor into reverse, one that won’t hold in reverse, and a VFD that runs while its motor just hums.

    Fixed

    • Overload current reading. An overload was also counting the current of anything fed through its 95-96 trip contact — in the DOL preset it read 4.7A instead of the motor’s 4A. It now only counts current through its three power poles, as a real thermal overload does.
    • An unpowered timer no longer drives anything. A timer’s NC output was live even when the timer itself had no supply, so a relay, lamp or second timer wired to it came on (and showed current flowing) before anything had operated. NC is now only live while the timer is powered and timing, and NO only once it has operated — and an on-delay timer’s output drops the instant its supply is switched off.
    • Shorts on device outputs are now detected: a timer, PLC or custom-block output wired straight to N, 0V or earth, or a transformer’s X1 wired to its X2, now raises a short-circuit alarm like any other short.
    • Parts can be moved anywhere. There was an invisible wall at the top-left of the work area, so parts in a new circuit or preset couldn’t be moved further up or left.
    • Each preset’s instructions now show in the side panel when you load it — they were being replaced by the general Edit-mode tips.
    • Parts can’t be added while simulating — the parts panel greys out until you switch back to Edit.
    • Timer and PLC outputs can now drive relay coils. A relay (or contactor) wired to a timer’s NO/NC output or a PLC output never pulled in, although a lamp in the same place lit. Device outputs are now live before the relays are worked out, so relays, contactors and even a second timer (for a cascade) can all be driven from them.
    • Relays and lamps no longer switch on with no voltage across them. In circuits where several lamps share a return wired to N, the simulator could find a false “supply” by tracing backwards through another lamp and the neutral bus, pulling in relays that should have stayed off. A point wired to N (or any rail) is now always held at that rail’s voltage. Thanks to the electrician who sent us their circuit.
    • A circuit with only a power side — for example a supply, a breaker and a motor — now exports as a power circuit drawing, instead of saying there’s nothing to export.
    • PDF export works with interlocked relay circuits. In circuits where several relays share a feed and their lamps share a return, the drawing tried to include every possible route — including ones back along the neutral — and ended up too big to draw. It now draws just the real paths: each relay’s button, and its seal-in through the interlocks. The voltage on the drawing now defaults to your control rail (e.g. 24V).
    • The VFD now trips on output faults, like a real drive: an output connected to earth, PE or 0V trips it with an earth fault (GF); two outputs connected together, or an output connected to a supply, trips it with an output short (SC). Reset on DI3 once it’s fixed. Help lists all the drive fault codes.
    • Alarms stay on screen until you acknowledge them. A short that only lasts an instant — like both contactors of a reversing starter pulling in together — used to flash up and vanish. It now stays, marked as cleared, and several alarms are listed together.
    • A motor that goes straight from one direction to the other without stopping (plugging) now raises a Motor reversed at speed alarm.
    • Fuses on a transformer’s secondary now blow. Loads fed from a control transformer weren’t being counted, so a 1A fuse feeding a 3A lamp off a 12V secondary never blew. They are now, and the primary side carries its share too (scaled by the transformer’s ratio), so a primary fuse sees it as well.
    • The current path through a transformer is now shown properly: in through H1 and back out through H2 to N on the primary, and out of X1, through the load and back into X2 on the secondary.
    • Current flow now goes the right way everywhere. Where two loads share wiring — like the RUN lamp across CR1 in the Start/Stop preset — the return side flowed backwards. Current now always runs from the supply, through the load and back to the return.
    • A wire that has voltage on it but carries no current — such as the one up to a released START button once the seal-in is holding — now shows still dashes instead of flowing.
    • A motor that loses one of its three phases (an open contactor pole, a broken cable) now single-phases: it hums, stalls and draws heavy current until the overload trips, instead of simply switching off.
    • PDF drawings now number every wire, including a lamp wired across a coil, and all wire numbers are the same dark blue. Line numbers sit in small boxes in the margin so they can’t be mistaken for wire numbers.
    • Drive and custom-block terminal names now sit inside the box, and motor U-V-W labels sit inside the motor, so incoming wires no longer run through them.

    Improved

    • When a new version comes out, a small What’s new card now appears in the corner of the app with the highlights and a link to this page. Close it and it won’t show again until the next update.
    • Neater wiring. Every wire now comes straight out of its terminal — left, right, up or down, whichever side the terminal is on — for a short run before it bends, like a properly dressed conductor. Wires no longer run behind components or double back on themselves, and they avoid lying on top of each other. The motor presets have been laid out to suit.
    • The feedback form can’t be sent empty any more, and if you tell us something went wrong, it asks you what happened — so we can actually fix it.
    • The website has a Follow menu at the top, and links in the footer, to our YouTube, TikTok, Facebook and X.

  3. 1.1.2

    PLC timers now work properly, with a live PLC monitor you can watch while the circuit runs — plus proper IEC or ANSI symbols and a motor that shows which way it turns.

    PLC — fixed

    • Timers now work. Clicking an instruction used to change its address, so selecting a timer quietly broke it — and a contact could never be set to read the timer (T0). Clicking now only selects, and a contact can read an input, an output, a timer or a counter.
    • A coil after a timer now waits for it. On a rung like I0 → Timer T0 → Q0, Q0 used to switch on straight away. Now it comes on only when the timer is done, and goes off when I0 drops.
    • Timers can no longer jump straight to done after switching back from Edit mode or another browser tab.
    • Timer and counter boxes now show properly in the ladder.

    PLC — new

    • Live PLC monitor. In Simulate, double-click the PLC and it opens as a small floating window you can move and resize (or click Live Monitor in the full editor). Watch the ladder scan, timers count and outputs switch while you operate the circuit.
    • Help has a new PLC Programming section covering the monitor, every instruction and the editor shortcuts.
    • Easier editing. Click to select, double-click (or Edit, or Enter) to set an address or preset, and press Delete to remove. Click a rung number to select the whole rung.
    • Latch and Unlatch instructions: turn an output on and keep it on until it’s unlatched.

    New

    • A Symbols switch in the bottom-right corner of the canvas changes the drawing between the panel view, IEC 60617 (Europe, UK and Ireland) and ANSI / NFPA 79 (North America) in one click. Contacts, coils, lamps and overloads still animate as the circuit runs, and your choice is remembered. Picking IEC or ANSI also sets the PDF export to match.
    • The motor now shows its direction of rotation: a cyan arrow for clockwise, amber for anticlockwise. Swap any two phases and the arrow flips, just like on a real motor, and the status reads CW or CCW.
    • New Forward / Reverse preset: a reversing starter with KM1 and KM2, seal-ins, FWD and REV lamps, and electrical interlocks, so you can watch the motor change direction and see why both contactors can never pull in together.
    • The overload relay has its own drawing symbol: three poles through thermal elements, linked to the 95-96 and 97-98 trip contacts, with the RESET button where it always was.
    • 3-Phase Supply block with labelled L1, L2, L3, N and PE terminals in their core colours (brown, black, grey, blue, green/yellow). Double-click it to change the voltage or reverse the phase sequence — the classic “supply swapped, motor runs backwards” fault. The DOL, Forward / Reverse and VFD presets now use it.
    • Earth Bar, and motors now have a PE terminal for the frame earth. Validate Circuit warns if a motor or drive isn’t earthed, and a live conductor touching earth is flagged as an earth fault.
    • Power circuit in the PDF. When your circuit has a 3-phase motor, the drawing now shows the power side too: L1, L2, L3 and PE across the top, each phase dropping through the breaker, contactor poles and overload (or drive) to the motor. The reversing starter shows its phase swap as a crossover.
    • Separate 400V rails can each carry one phase: name them brown, black and grey (L1, L2, L3), or set the phase by double-clicking the rail.
    • IEC drawings show terminal markings: A1-A2 on coils, 13-14 and 21-22 on contacts, 1-2 / 3-4 / 5-6 on contactor poles and 95-96 on the overload.
    • ANSI drawings use North American symbols throughout: parallel-plate contacts, circle coils, pushbuttons with a bridging bar, pilot lights with a colour letter.

    Fixed

    • A 3-phase motor now needs three different phases to run. Feed it two on the same phase and it single-phases: it stalls, draws heavy current and trips the overload. All three on one phase and nothing happens — just like a real motor.
    • The moving current-flow dashes now always run from the supply towards the load, however the wire was drawn.
    • With an open neutral, the multimeter now reads the voltage across the break, the way a real meter would, instead of a false short or “both at 0V”.
    • IEC coils are drawn the right way round, with the wires on the long sides, so a coil no longer looks like a resistor.
    • IEC timer coils use the standard delay box (a cross for on-delay, filled for off-delay), and the overload trip contact uses the thermal actuator symbol.
    • Selector switches show their turn actuator, and pushbuttons keep theirs on I/O field wiring drawings.
    • Timers are tagged KT in IEC drawings, because T means transformer.
    • Choosing ANSI in PDF export no longer mixes in IEC symbols for fuses, overloads, breakers, lamps and emergency stops.
    • PDF drawings no longer repeat the whole STOP/START path for every seal-in or lamp. Seal-ins are drawn as parallel branches, lamps on a coil share its rung, and forward and reverse branch off a single STOP, the way a real ladder diagram is drawn.

    Improved

    • Short-circuit and trip alarms float higher up over the canvas, centred on your circuit, instead of sitting on the bottom edge of the window over the Sequence Log.
    • Help has a new Drawing Symbols section explaining the Panel, IEC and ANSI views and how to read terminal numbers, plus notes on motor rotation and the Forward / Reverse preset.
    • A What’s new link at the top of Help opens this page. After an update, a small green dot on the Help button lets returning users know something has changed.
    • The canvas and the PDF export share one symbol set, so what you draw is exactly what prints.
    • Lamp colours are written on the drawing (RD, GN, YE), so they still read on a black-and-white print.
    • Pushbutton, e-stop and selector labels no longer sit on top of the button. The button moves to the corner and the name gets its own space, shrinking or trimming if it’s long. Lamp labels no longer blur in the lamp’s glow.

  4. 1.1.1

    Loads and shorts now behave the way they would on a real panel.

    Fixed

    • A lamp or coil with a live feed but no neutral or return no longer lights up or pulls in. A load now needs a complete circuit, the same as on a real panel.
    • A dead short to neutral is now flagged in normal mode, not only in Strict Mode. The shorting path is traced in red on the drawing, and the alarm clears once the short is removed.

    Improved

    • In the Start/Stop example, the RUN lamp now sits on its own rung under CR1, so it clearly reads as wired in parallel with the coil rather than in series.

  5. 1.1.0

    Save your work, practise fault finding, and share circuits with a link.

    New

    • Your circuit saves automatically. Come back later and you can pick up where you left off.
    • Ten guided fault-finding challenges. Your progress is kept on your own device.
    • Share a circuit as a link. Whoever opens it sees exactly what you built, with no account needed.

    Improved

    • Fault injection now has its own button in the main toolbar, so it's easier to find.

    Fixed

    • A relay or contactor fed through a timer contact now pulls in when the timer times out.
    • Circuits with a timer no longer report a short circuit that isn't there.

  6. 1.0.0

    First public release: control circuits, DOL starters, VFD drives and 3-phase motors, fault injection, a phase-aware multimeter and IEC-style PDF export, free in the browser.

    Added since launch

    • An anonymous feedback form inside the app. No email needed.

    Fixed since launch

    • Pressing keys while a dialog is open no longer changes the circuit behind it.