Veichi AC310 Service Manual page 16

current reaches the set overcurrent point, which is connected to the FAU pin to protect the
system from SC; and using the slow protection pins VOC_S and FAULT_S/, the
corresponding OC signal is pulled low, causing the COLSE signal to go high and blocking
the outputs. When the current reaches the set overcurrent point, the chip sends out a low-
level signal of FAULT within 1.5us, and connects this signal to the FAU pin to protect the
system from SC.
2. Fault type
E.HAL, E.OL2, E. OC, E.OLF
3. Detection method
Static detection
(Note that the current detection chip ACS720 is on at pins 1 to 8 during measurement
because the detection chip is differential current detection, which can well suppress external
magnetic field interference). (Note that pins 1 to 8 of the current detection chip ACS720 are
energized during measurement because the detection chip is a differential current detection chip,
which can well suppress the interference of external magnetic field)
Dynamic detection:
When powering up, look at pin 14 of the current detecting chip to see if there is 5V voltage,
pin 12 and REF pin correspond to 1.5V, which corresponds to 5V at pins 13, 15, and 16 when
normal, if the output voltage of pin 12 is abnormal when other voltages are normal, then the
current detecting chip is abnormal.
4. Damage-prone devices ICs, op amps
5. Device bit number and specification
Capacitors
C31/C37=1nf/0805
C14/C62/C33/C34=100nf/
0805 C32/C38=1uf/0805
C35/C36/C55/C54=330pf/
0805
Sampling chip
U3/U5=ACS720KLATR-65AB-T
AC310 Universal AC Drive Service Manual
Resistive
R30/R69/R70/R86/R87/R37=5101
/0805
R7/R36/R74/R76/R90/R92=4701/
0805
R78/R81/R38/R39=2000/0805
Op amp
R75/R77/R91/R94=1002/0805
U4=LF353DRG4
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