Black Box 32144, Manual

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APPENDIX D: DC Voltage Models
Appendix D: DC Voltage Models
D.1 Introduction
The modems with codes MD833A-D12, MD833A-D24, and MD833A-D48
are pre-configured for DC voltage operation. The MD833A-D12 is pre-
configured for use with a -12 VDC power source, the MD833A-D24 is pre-
configured for use with a -24 VDC power source, and the MD833A-D48 is
pre-configured for use with a -48 VDC power source.
This addendum provides installation and jumper information for the
DC pre-configured modems for applications where an external DC power
source will be used (i.e., not DC power provided from a rack enclosure).
If the modem is to be installed in a rack, refer to the instruction manuals
for the modem and the rack.
CAUTION
The -48 VDC model should be used only with an external DC power
source.
For modems using an external DC power source, the information in
this addendum about installation and jumper settings supersedes the
information in the rest of the Modem 32144 manual. However, all other
information in the instruction manual is applicable.