This DC Power Module is designed for use in the Total Access 1500 Chassis. It converts unregulated -42 VDC to -56 VDC input power to +5, +3.3, -7.5, and -24 VDC used by the common modules and access modules of the Total Access 1500 system. It is designed to use an external ringing supply. Two modules may be installed in either chassis to provide fully redundant operation. The module does not require provisioning prior to insertion into the chassis.