Daktronics AB-1600-1.5,2.5 - Manual (Page 30)

3-14 Electrical Installation
Venus 4600 System:
The display will blank until a sequence is run on the controller.
8. When the test patterns are done the Venus 1500 controller will run messages stored
in the battery backup memory. These messages will continue to run until the power
is turned off or the messages are changed using the programmer’s console.