Section 150-441-124
June 12, 1997
Revision 01
Page 6
PairGain Engineering - Plant Series
HiGain HLU-D41
the payload. An 8-bit microprocessor is used to monitor and control the HLU-D41.
Provisioning status information is provided either through the HLU-D41 Maintenance Terminal
menus or the front panel Mode and Choice Setup buttons, to the microprocessor. The micro-
processor communicates with the HDSL framer for signal status and configures the circuit
bandwidth at the DS0 channel interface.
5. Power Consumption and Powering the Remote Unit
5.1
The primary power demands of an HLU-D41 on the channel bank power supply are listed in Table 4
on a per slot basis.
Table 4. Power Consumption and Power Dissipation
Power*
Per Slot
Maximum Power Consumption
Line-powered remote unit
14 W
Locally-powered remote unit
10 W
Maximum Power Dissipation
Line-powered remote unit
6 W
Locally-powered remote unit
3 W
The worst case conditions under which these parameters are
measured include a 9,000 ft., 26 AWG loop configuration.
5.2
The maximum number of channel bank slots that can be occupied by HLU-D41 units is a function of
the type of bank and the capabilities of its common power supply. The limiting factor is the drain on
the bank’s +5V power supply. The HLU-D41 draws 295mA of +5V power when the HRU is locally
powered and 325mA when the HRU is line powered. The worst case +5V current drain for D4
common equipment is 1.2A.
5.3
Line and Local Powering of the Remote Unit.
The HLU-D41 is designed to either power the
HRU-512 over the HDSL cable pair, or allow the HRU-512 to be powered from the remote end. The
HLU-D41 determines the power state of the HRU-512 before attempting to apply line power:
If the HRU-512 is remotely powered, the HLU-D41 does not apply line power.
If the HRU-512 is not remotely powered, the HLU-D41 applies power to the HRU-512 over the
HDSL cable pair.
The line power supply can be turned on or off by using the PWRF (power feed) system option setting
and is automatically shut down in the presence of line short circuits or a microprocessor failure.
The HRU-512 also provides from 14 mA (long loop) to 16 mA (short loop) of metallic sealing
current toward the HLU-D41, when the HRU-512 is locally powered. To enable the sealing current
capability when the HRU-512 is locally powered, connect JP2 across both terminals.
To configure the system for HLU-D41 line powering
1
At the HRU-512, connect JP2 across just one of the two terminals. These are the factory default
settings.
2
Enable the PWRF option setting using the front panel setup buttons, or the Maintenance
Terminal menus using the POWER option in the System Settings menu.
