Emergency guide · 5 min read

Your HMI panel just died.
The line doesn't have to stop.

The good news nobody tells you in the first panicked hour: the PLC that actually runs your machine is almost certainly still fine. The panel is just the window. Here's how to confirm that in 10 minutes, what your real options cost, and how to keep producing while the proper fix is on its way.

Line down right now? Request a free remote triage call →

First: the 10-minute triage

Before anyone orders anything, work through this list. A surprising share of "dead panels" turn out to be something cheaper.

  1. Is the machine still running? If yes — the PLC is healthy and this is a visibility problem, not a control problem. Breathe.
  2. Panel power. Check the 24 VDC supply feeding the panel and its fuse. Panel power supplies fail far more often than panels.
  3. The flashlight test. Screen black but the power LED is on? Shine a flashlight at the screen at an angle. If you can faintly see the picture, the backlight is dead — the panel itself works, and a backlight/display repair is much cheaper than a replacement.
  4. Communications. If the panel boots but shows comm errors, check the Ethernet cable, the switch port and the PLC's link LEDs. The panel may be fine.
  5. One clean power cycle. Remove power for 30 seconds, restore it, let it boot fully. Firmware lockups happen; one restart is diagnosis, not superstition.

Still dead after all five? Now it's a real panel failure. Here are your options, honestly.

Your real options (with honest timelines)

OptionTypical costTypical timeWatch out for
Repair service (backlight, touch, PSU)$300–$1,0001–2 weeks + shippingLine is dark the whole time
Used unit (eBay etc.)$500–$2,500Days, if you're luckyNo warranty, unknown hours, config transfer still needed
New replacement panel$1,500–$4,0002–6 weeks lead timePlus converting & downloading the panel project
Bridge device (keep producing meanwhile)$1,290 one-time (founders' price)First batch — line-down requests get the first units + a free triage call nowMinimal by design — key values and buttons, not full HMI graphics

These paths combine. The plants that lose the least money usually order the proper repair or replacement and bridge the gap so the line produces while they wait.

How the bridge works

LineKeeper is a self-contained 7″ touchscreen that plugs into the same network as your Allen-Bradley ControlLogix or CompactLogix. It reads the controller directly — the PLC program is never modified.

  1. Plug in — power + Ethernet into the machine network.
  2. Type the PLC's IP address — every tag appears automatically, live, twice a second.
  3. Assemble the operator screen — drag-and-drop the start/stop buttons, indicators and setpoints your operator needs. No programming, no licensed engineering software.

Afterwards it stays useful: data logging, dashboards, and diagnostics for the machine — many plants keep it running next to the new panel. See the full product tour →

We're honest about availability. We're a young company and the first production batch is being prepared right now. Joining the early list is free; line-down requests go to the very front of it, and every request starts with a free remote triage call — often we can point you to a workaround that gets you producing before any hardware arrives. Founders' price for the list: $1,290 (reg. $1,490), 30-day money-back guarantee.
FAQ

Line-down questions

Can the line legally/safely run without its HMI?

The PLC keeps executing its program and all safety logic regardless of the panel. What you need is visibility (values, alarms) and control (start/stop, setpoints) — that's exactly what a temporary HMI restores. Your own safety procedures and local regulations still apply, of course.

Will it work with our controller?

Today LineKeeper supports Allen-Bradley ControlLogix and CompactLogix over EtherNet/IP — tags, UDTs, arrays, timers, counters, I/O modules, discovered automatically. Before shipping we confirm your exact controller model. 30-day money-back guarantee if it doesn't work out.

We need it faster than you can ship. What can you do?

Tell us the line is down: you go to the very front of the list for the first available units, and the triage call is free regardless of whether you buy. If your replacement panel arrives first — great; the early-list spot costs nothing and cancelling is one email.

Do we need IT or an integrator to set it up?

No. If someone on site can type an IP address, they can connect it. The operator screen is drag-and-drop, and the included one-page guide is written for line staff.

Get help now

Tell us what died

Line-down requests are answered first — usually within a few hours. The triage call is free; reserving a unit costs nothing.