A programmable LED text board displays changing lines of text: prices, opening times, a rate, a delivery day, a shift notice. It is our least expensive product and the one most often bought without asking the operational questions. Below, those questions come first, and the answers are specific about power, environment, failure behaviour and remote diagnosis.
LED scrolling sign in Velika Gorica — manufacturing, installation, quote
A text board on the airport approach at Pleso, or on a workshop gate in Kurilovec, is a machine that runs unattended for eighteen hours a day, three hundred and sixty-five days a year, in weather that ranges from freezing fog to thirty-five degrees. Nobody watches it. Nobody notices when it goes wrong except the customers who stop trusting it. That makes reliability, not content, the interesting engineering question in Velika Gorica, and it is the one this page concentrates on: what the device draws, what happens inside its case on a wet November morning, how it behaves after a power failure, and whether a fault can be understood without somebody driving 313 kilometres to look at it.
What is actually running when nobody is there?
Controller, schedule and the state after midnight
The board is not a screen waiting for a computer. The controller holds the message list, the schedule and the brightness curve in its own memory and executes them independently, which is why a board keeps working when the office network is down or the laptop that programmed it has been reformatted. Messages carry validity windows, so a promotion set to expire on the thirtieth genuinely stops on the thirtieth. The consequence worth planning for is the opposite one: a board with no schedule will happily display last spring's line until somebody notices, and nothing in the machine will complain about it.
How much electricity does a text board really use?
Peak, average and the difference between them
A text board lights a small fraction of its pixels at any moment, because text is mostly background. Its average consumption is consequently a small proportion of the peak figure on the data sheet, and far below that of a full-colour video display of the same area. In practical terms, a single-line board of a couple of metres in length costs very little to run over a year, and the dimming schedule that lowers output after dark takes a further slice off. The peak figure still matters for one reason only, which is sizing the circuit and the power supply, and there we design with headroom rather than to the number.
What happens inside the case on a foggy morning?
Condensation, ventilation and the IP65 enclosure
Outdoor units are sealed to IP65 against rain and dust, but a sealed box in the fog belt that settles over Velika Mlaka and the fields towards Novo Čiče has a second problem: moist air that entered while the case was warm condenses on the inside of the face as the temperature drops overnight. The answer is not more sealant. It is a housing designed with drainage at its lowest point and pressure equalisation, cable entries with proper glands, and mounting that leaves an air gap behind the unit rather than trapping it against a cold wall. Boards mounted behind glass indoors avoid all of this and can run at much lower output, which is why a window unit is usually the cheaper and longer-lived choice where it is an option.
How does the board behave after a power cut or a surge?
Restart, memory and protection on the supply
On restoration of power the controller restarts and resumes the schedule by itself, with no reloading and no lost settings. Surges are the more serious threat, particularly on a rural feed and on anything mounted high with a long cable run, and the protection belongs on the supply side where an electrician can inspect and replace it. This is worth insisting on: the single most common cause of a dead outdoor board that we are called to is not the diodes, which almost never fail as a group, but the power supply, and a power supply that failed because nothing protected it.
Can a fault be diagnosed without a 313 kilometre drive?
What can be checked remotely, and what cannot
Whether the unit stands on a forecourt at Kurilovec or above a doorway on Trg kralja Tomislava, a controller with network or Wi-Fi coverage can be reached remotely, and a surprising share of reported faults turn out to be a schedule that expired, a brightness setting at zero or an address changed by a router replacement. Those are fixed in minutes from Győr. What cannot be done remotely is anything physical: a failed supply, water ingress, a damaged ribbon between modules. For those we travel, and 313 kilometres is a same-day return journey, so a call on Tuesday is normally attended that week. Sending photographs of the fault beforehand decides which spare parts come in the van.
How is the display kept from becoming a nuisance at night?
Dimming, colour and the settings we record
A single-colour board driven at full output for daytime sun is uncomfortably bright at midnight, particularly in a street with housing. The brightness curve is set at commissioning against the actual position, not against a default, and we record the values in the handover documentation so they survive a controller change. Scroll speed matters here too: fast movement in peripheral vision at night is more irritating than the light level itself, and holding text statically for a few seconds is both calmer and better read.
