NetApp DS4246 User Manual

V
LOAD
= I R
TEST
I = V
LOAD/
R
TEST
V
OC
= V
SOURCE +
V
LOAD
V
OC
= IR
S +
V
LOAD
R
S
= V
OC -
V
LOAD
I
R
S
= (V
OC -
V
LOAD
)
V
LOAD
/R
TEST
R
S
= V
OC -
V
LOAD
V
LOAD
=
48V - 47.5V
47.5V
= 0.105
R
TOTAL
= R
CABLE
+ R
SOURCE
R
CABLE
= R
TOTAL
- R
SOURCE
R
CABLE
= 0.233 - 0.105
= 0.128
Solution
V
DROP
= I
MAX
R
TOTAL
2
= 8.6 R
TOTAL
R
TOTAL
= 2/8.6
R
TOTAL
= .233
x
R
TEST
x 10
For example, if you have a 12-gauge wire, solid strand, at room temperature, you use the following
calculation:
Total cable length =
Total cable length = = 75 ft
R
CABLE
DC resis.
1
.128
.0017 /ft
AWG
Strand DC resistance
1
[Ω/ft.] Total cable length
2
[ft]
25°C 75°C 25°C 75°C
12 Solid .0017 .0020 75 64
DS4243, DS2246, DS4486, and DS4246 Installation and Service Guide 66
Recommended power line sizes

NetApp DS4246 Specifications

General

Data transfer rate	6 Gbit/s
Storage drive size	3.5 \
Storage drive interface	Serial Attached SCSI (SAS)
Storage drives installed	Yes
Installed storage drive type	HDD
Supported storage drive types	HDD & SSD
Total installed storage capacity	40.8 TB
Maximum supported storage capacity	- TB
Number of storage drives installed	24
Chassis type	Rack (4U)
Product color	Black
Device class	Large Enterprise Business
AC input voltage	100-240 V
AC input frequency	50 - 60 Hz
Number of power supply units	2
Operating altitude	0 - 3045 m
Non-operating altitude	-305 - 12192 m
Storage temperature (T-T)	-40 - 70 °C
Operating temperature (T-T)	10 - 40 °C
Storage relative humidity (H-H)	10 - 95 %
Operating relative humidity (H-H)	20 - 80 %

Weight and Dimensions

Depth	610 mm
Width	483 mm
Height	178 mm