23
2
Installing Power Cables
NEG2(-)
INPUT
RTN2(+)
RTN1(+)
NEG1(-)
ON
OFF
20A
32A
32A
20A
ON
OFF
1
2
3
4
1
2
3
4
20A
32A
32A
20A
OUTPUT
OUTPUT
A
B
RTN(+)
NEG(-)
Check the fuse current of the external
power supply.
Check the voltage and polarity of the external power
supply.
Recommended Current Value of the
External Fuse
20 A
Rated Voltage of the Input
Power
Allowable Voltage Range
–48 V ( DC )
–38.4 V to –57.6 V ( DC )
–60 V ( DC )
–48 V to –72 V ( DC )
The recommended fuse capacity of 20 A can meet requirements under the maximum power consumption. Customers
can compute the fuse capacity according to the actual power consumption. The fuse capacity should be larger than or
equal to (total power consumption x 1.5)/(rated voltage x 87.5%). For example, when the rated power supply is -48 V and
the total power consumption of the IDU is less than or equal to 420 W, the fuse capacity can be set to 15 A.
NOTE
Insert the power cables into the DC connector based on the pin assignment. You do not need to prepare the
power cables on site if they were prepared before delivery.
After fastening a cable, check whether the cable core is exposed outside the power cable connector
terminal. If the cable core is exposed, re-route the cable into the power cable connector. If the cable core
is still exposed after you re-route the cable, peel the cable again.
CAUTION
If the AC power box (ETP 4830) is used, the IDU needs to use the BGND power cable and -48 V power cable that are
delivered with the AC power box. For details on the AC power box and its cables, see the IDU hardware description.
1
1
WARNING
The IDU does not support AC power. Do not connect the IDU to
an AC power supply. Otherwise, equipment may be damaged
and you may be injured.
