Section 150-388-124
Revision 01
Page 37
TABLE 11. HLU-388, LIST 2D DOUBLER POWER PARAMETERS
60 mA CPE
Current
CO Voltage
Volts
CO Current
Amps
Power Consumption
Watts
HLU Power
Dissipation Watts
Doubler Models
HDU-439/437
OFF
42.50
0.50
21.5
8
also HDU-451
List 1, 2, 3, 4
OFF
48.00
0.44
21.5
8
List 1, 2, 3, 4
OFF
56.00
0.38
21.5
8
List 1, 2, 3, 4
ON
42.50
0.6
25.5
9
also HDU-451
List 3, 4
ON
48.00
0.53
25.5
9
List 3, 4
ON
56.00
0.45
25.5
9
List 3, 4
18.05
The power consumption listed in Table 11 is the
total power that the HLU-388, List 2D consumes
or draws from its -48 Vdc shelf power source. This
parameter is needed when the HLU-388, 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-388 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.
19.03
“GNLB” is the HiGain system Generic Loopback
code. The GNLB allows in-band codes from the
network to loop up either the HLU/NLOC (4 in 7) or the
HRU/ NREM (3 in 7) toward the network. In addition, it
allows in-band codes from the Network Interface (NI) to
loop up the HLU/CREM (6 in 7) or the HRU/CLOC (5 in 7)
toward the customer. For doubler applications, it permits
looping doubler number 1 toward the network NDU1 (2 in
6) or toward the customer CDU1 (4 in 6). Doubler number
2 is looped toward the network with NDU2 (3 in 6) or
toward the customer with CDU2 (5 in 6). Either loop-up
condition is terminated (looped down) with the (3 in 5)
loop-down code. All messages must be present for five
seconds before the HiGain system will respond. Table 12
lists the test procedures that apply when using the GNLB
mode.
