Section 150-319-124
Revision 03
Page 38
TABLE 11. HLU-319, LIST 2D POWER PARAMETERS WITH HDU-451
60 mA CPE
Current
CO Voltage
Volts
CO Current
Amps
Power
Consumption
Watts
HLU Power
Dissipation Watts
HDU-451
Doubler Models
OFF
42.50
0.50
21.00
8
HDU-451, List 1-4
HDU-439/437 List 1
OFF
48.00
0.44
21.00
8
HDU-451, List 1-4
HDU-439/437 List 1
OFF
56.00
0.38
21.00
8
HDU-451, List 1-4
HDU-439/437 List 1
ON
42.50
0.6
25.5
9
HDU-451, List 3 & 4
HDU-439/437 List 1
ON
48.00
0.53
25.5
9
HDU-451, List 3 & 4
HDU-439/437 List 1
ON
56.00
0.45
25.5
9
HDU-451, List 3 & 4
HDU-439/437 List 1
18.05
The power consumption listed in Table 11 is
the total power that the HLU-319, List 2D consumes
or draws from its -48 Vdc shelf power source. This
parameter is needed when the HLU-319, List 2D is
remotely located to its serving CO. It determines the
battery capacity required to maintain an 8-hour
standby battery reserve for emergency situations. It
thus limits the maximum number of plugs per remote
enclosure. Use this data to perform this analysis on a
case-by-case basis.
18.06
The maximum Current Drain is the maximum
current drawn from the shelf power supply when it is
at its minimum voltage (-42.5 V). It determines the
shelf fusing requirements. All HLU-319 shelves are
partitioned into two equal halves, each fused at 10
amps for a total of 20 amps per shelf. A fully loaded
shelf draws 17 amps worst case (8.5 amps per fuse).
This is within the 20 amp fuse limit.
18.07
Heat baffles should be placed between every
other shelf, in racks containing more than two shelves.
This technique deflects the rack heat outward and
reduces thermo stress on the plugs.
19. LOOPBACK OPERATION
19.01
The HiGain system has a family of loopback
options. The most important of these is the Smart-
Jack loopback which enables the HRU-412 to respond
to the standard (2/3 in 5) Smart-Jack in-band
loopback codes. This option can be ENAbled or
DISabled from either the front panel settings or the
terminal System Settings Menu screen.
19.02
In addition to the Smart-Jack loopback, the
HiGain system can be configured for one of five
special in-band loopback (SPLB) command
sequences. These are selected from the SPLB user
options shown in Table 1. The loopback locations are
shown in Figure 15.