Theory Of Operation; Dc Auxiliary Power Circuit; Auxiliary Power Failure Detection - Tripp Lite SU60KX Manual

2 Theory of Operation (continued)
2.2 DC Auxiliary Power Circuit (continued)
Located at NH-SYS-M board (System MCU and Control Circuit)
RM 42
5VS
K-ON
(a) The input of DC auxiliary power circuit is from positive battery.
(b) MCU detects the "on" key (on LCD board) status through KEY-ON(21)
(c) When AC auxiliary power circuit is activated and battery is present, AUXON (64) is high and DC auxiliary power circuit will be on.
(d) If AUXOFF (44) is high during backup mode, DC auxiliary power will be off.

2.3 Auxiliary Power Failure Detection

Located at NH-SYS-P board (Auxiliary Power for System, Detect Circuit for Voltage and Current)
Located at NH-SYS-M board (System MCU and Control Circuit)
+12VP is from AC auxiliary power and +12VB is from DC auxiliary power. During AC mode, +12VP and +12VB should both be live. If one or
both of them fails, MCU can detect auxiliary power failure through AUXFAIL (71) (low active).
RM 43
KEY_ON
(21)
CM 24
G1
+12VS
RP18
+12VB
ZDP5
+12VS
RP21
+12VP
ZDP6
RM 34
5VS
AUX-FAIL
AUXON
(64)
AUXOFF
(44)
DP11
RP20
QP8
RP19
AUX-FAIL
G1
DP12
RP23
QP10
RP24
QP9
RP22
G1 G1
RM 35
AUXFAIL
(71)
CM 23
G1
51
RM 22
AUX-ON
RM 26
AUX-OFF