Allmand Brothers MB 6200 - Manual (Page 47)

47
Connecting Power to BRICK system
1. Connect 12 VDC to the single-board computer (SBC).
2. The size of a power supply is generally specified by the total continuous power output capability. This is
usually given in Watts but may also be stated in current (Amps).
Power Supply
Rating Per
BRICK (see
definition
below)
Absolute Maximum
Current Per
BRICK (see
definition below)
Typical Maximum
Current Per
BRICK (see
definition below)
Average 24-
Hour Current
Per BRICK
(see definition
below)
BRICK:
High
Density
55 Watts 4.8 Amps 3.1 Amps 11.5 Amps
BRICK:
Standard
Density
15 Watts 1.75 Amps 0.7 Amps 3.5 Amps
Definition of BRICK operating parameters shown in previous table:
Power Supply Rating – Amount of power (Watts) needed per BRICK. This is a general rule of thumb to
allow for the potential of powering all LED pixels at full brightness.
Absolute Maximum Current – Current limit setting on a BRICK resulting in the worst case current draw in
the event of a failure.
Typical Maximum Current – Current draw for a BRICK in maximum ambient light conditions with all of the
pixels lit.
Average 24-Hour Current – Current draw over 24 hour day (assume 12 hours daytime, 12 hours nighttime)
with an average text based display that utilizes approximately 30% of the LEDs pixels for High Density
BRICKs, 40% LEDs for Standard Density BRICKs.
Wire Size Calculation
3. The wiring tables below are for general guidelines. All wiring and circuit protection devices should meet
National Electric Code (NEC) requirements. Wire size is important for two basic reasons: to meet proper
current carrying capacity defined by NEC and to minimize voltage drop for optimal performance. To
determine the wiring size required, find the total current using the following formula:
Total Current = Number of BRICKs × Absolute Maximum Current (table above)