
EDIT.
SHEET
DRAW. NO.
CUST.
TITLE
84
93
DESCRIPTIONDESIG.DATE
Power Failure Backup Module
Descriptions
A-53866E-464
8.2.1 Calculating the Amount of Energy That Can Be Supplied Per Sub module C
Sub module C is charged to about the same voltage of the DC link voltage at all times through the charge
circuit inside the power failure backup module. The amount of energy per
sub module C depends on the
voltage of the sub module C before
a power failure occurs (≅ PSM input voltage × 1.41), and is
determined with expression <2>.
For the A06B-6077-H010 (for 200V)
)
3
108.9
2
1(
2
105.21 ×−×
−
×= VW
------ Expression <2>
For the A06B-6083-H245 (for 400V)
)
4
102.4
2
1(
3
105.41 ×−×
−
×= VW
------ Expression <2>
W1 [J]: Amount of energy per sub module C
V1 [V]: PSM input voltage before a power failure occurs
The table below gives examples of the relations between the PSM input voltage and the amount of energy
W1 that can be supplied per sub module C.
A06B-6077-H010 (for 200V) A06B-6083-H245 (for 400V)
PSM input voltage
V1
Energy amount W1
PSM input voltage
V1
Energy amount W1
AC170V 478J AC340V 330J
AC200V 755J AC400V 530J
AC240V 1195J AC480V 850J
As the table above indicates, the amount of energy that can be supplied from sub module C varies
considerably depending on the PSM input voltage. This means that as the PSM input voltage before a
power failure occurs decreases, the number of sub modules C to be connected to obtain the same energy
increases.
When determining how much input voltage fluctuations should be considered, consider the power
condition.