COB Beta P1.5 Sand Table Display in Shanghai

The question wasn't whether P1.5 could deliver the visual quality. It was whether P1.5 could survive the installation — and the re-installation after that.

A corporate showroom operator in Shanghai wanted an L-shaped digital sand table — กว้าง9.6เมตร, consisting of a 30.72 m² floor display and a 23.04 m² LED wall rising behind it. The brief was straightforward: an immersive digital canvas where the floor layer renders GIS maps, floor plans, and 3D terrain models, while the vertical wall plays brand narratives synchronized with the sand table content.

But here's the rub: P1.5 at 54 m² means roughly 24 million pixels spread across 1,050 individual LED modules. Each module is a palm-sized board covered in tiny LED chips spaced 1.5 millimeters apart. At this density, a single LED die is barely visible to the naked eye — and just as fragile. SMD modules at P1.5 are notorious for losing pixels during assembly. A technician's fingertip pressing on the wrong spot, a screwdriver slipping, or modules stacked face-to-face during transport — any of these can shear off multiple LED chips in an instant.

And this client's showroom operates on a rotating exhibition schedule. The sand table would be assembled, disassembled, and reassembled multiple times. Each cycle with SMD would be a dice roll on dead pixel count. Each dead pixel requires removing the module, desoldering the broken chip, soldering a replacement, and recalibrating — a process that, repeated across a thousand modules, turns maintenance into a full-time job.

53.76 m² at P1.5mm pitch generates approximately 24 ล้านพิกเซล — the equivalent bandwidth of three simultaneous 4K streams running at 60Hz. A single standard LED sending card handles at most 8.84 million pixels (one MCTRL4K), so the math dictated a minimum of three units.

But raw pixel count isn't the only bottleneck. Each gigabit Ethernet output from a sending card maxes out at roughly พิกเซล 650,000 under standard 8-bit/60Hz conditions. For 24 million pixels:

เราได้ทำการติดตั้งระบบแล้ว three NovaStar MCTRL4K processors with a sync card to maintain frame-level synchronization across all three units. The topology splits logically: two MCTRL4K units drive the floor sand table (30.72 m² ≈ 13.7M pixels), and the third handles the vertical LED wall (23.04 m² ≈ 10.2M pixels). The sync card ensures both surfaces display the same frame simultaneously — so when a camera pans across a 3D city model on the sand table, the brand video on the wall transitions in lockstep.

On the receiving side, MRV336 receiver cards (256×256 pixel capacity each) were distributed across the 1,050 COB Beta modules. Each receiver card drives two modules, with 37 active Ethernet ports each feeding 14–15 receiver cards — well within the recommended load per port. This conservative distribution means no single port is at risk of frame drops even under peak content load.