How to Choose the Right Digit Size for Your Monolith
Get the digit height right and a passing motorist reads your price in one glance — get it wrong and the most expensive sign on the forecourt goes unread.
The single most important spec on a fuel-price monolith is one you rarely see on a datasheet: how tall the digits are. Digit height — not the size of the cabinet, not the number of grades, not even brightness — is what decides whether a driver can read your price while still far enough out to choose your station and slow down safely. This guide walks through how AVS sizes the digits on a Price Change Unit (PCU), and the real-world factors that push the number up or down.
Legibility is a function of height vs. distance
Sign legibility scales with character height. A useful field rule of thumb: for every 25–30 mm of digit height you gain roughly 30 m of comfortable read distance in good conditions. So a 300 mm digit is legible to most drivers from around 300 m out; a 180 mm digit closer to 180 m. Treat this as planning guidance, not a guarantee — actual performance depends on eyesight, weather, sun glare, ambient clutter and how cleanly the price contrasts against the cabinet face.
That is exactly why AVS keeps contrast high: red is the default LED colour, characters sit on a UV-resistant black silicone plotting face, and a 64-level auto photocell dims the display so it never blooms at night or washes out at noon. The numbers stay crisp across the full read range rather than only at one light level.
The AVS digit range: 120 mm to 600 mm
AVS PCUs are built with digit sizes from 120 mm up to 600 mm, in either Multi-Segment or 7-Segment fonts. The 7-Segment font is the classic block numeral — clean and economical. The Multi-Segment font uses more LED segments per character, giving smoother, rounder digits that read better at distance and look more premium on a flagship monolith. Both run on Cree or Osram LEDs (SMD or DIP), wired no more than two in series, in an aluminium-extrusion or HDPE casing rated IP54 or IP67 with a wide 120° viewing angle so the price stays readable from acute approach angles, not just head-on.
What pushes the digit height up or down
Before settling on a number, weigh these together — rarely does one factor decide it alone:
- Road speed & sightline. Faster roads need earlier reads. A driver at 90 km/h covers 25 m every second, so the price must be legible far enough out to react — bigger digits.
- Monolith setback. A totem set well back from the carriageway adds distance the digit must "reach"; a sign right at the kerb can run smaller.
- Number of fuel grades. Three or four grades stacked on one face limits the height each price can use within a fixed cabinet — size the cabinet around the digit, not the other way round.
- Single vs. double-sided. Double-sided totems face both traffic directions; each face may have a different approach speed and setback, so they are not always sized the same.
- Colour & day-night. Red is default; White or Dual-Colour (red by day, white by night, auto-switching — as deployed at Vivo Indonesia) can change perceived contrast and therefore effective read distance.
- Font choice. Multi-Segment digits read marginally further than 7-Segment at the same nominal height thanks to denser, smoother strokes.
A quick sizing reference
Use the table below as a starting point, then let the site survey refine it. Read distances assume clear conditions and a clean line of sight.
| Digit height | Typical use | Approx. read distance |
|---|---|---|
| 180 mm | In-station / low-speed forecourt entry, kerbside totems | ~180 m |
| 300 mm | Urban roadside monolith, moderate-speed arterials | ~300 m |
| 450 mm | Major roads, larger setback, multi-grade flagship totem | ~450 m |
| 600 mm | Highway frontage / high-speed approach, maximum reach | ~600 m |
Let AVS spec it for you
There is no public price list and no one-size digit — the right height comes out of your specific approach speed, setback, grade count and cabinet dimensions. Send AVS your monolith drawings or a photo of the location and our engineers will recommend the digit height, font, colour and PCU configuration to match, then quote the build. Every unit is wireless and controllable by 5-button remote, Price Sign Terminal, or full POS/IFSF integration so prices stay in sync with the pump.
See the full Price Change Unit specs, browse our installation guides, or request a quote with your site details.
Not sure which digit size your site needs?
Send us your monolith drawings or a forecourt photo and we'll spec the digit height, font and PCU configuration for your approach.