The Expandable POTS plug-in card (Model 751322), the POTS add-on card (Model 751322/1), and the Dual POTS plug-in card (Model 751322/2) provide high voltage isolation for an incoming telephone line at a power substation. Applications include telephone, dial-up modem, fax, and loop start PBX trunk.
- The Expandable POTS plug-in card 751322, isolates one POTS circuit. It is compatible with all Teleline Isolator 3-, 5-, and 8-card shelves CLEI number: NPP1WP0BAA
- The Add-on card 751322/1 can be installed on the Expandable POTS plug-in card (Model 751322) to upgrade from a single-line isolator to a dual-line isolator CLEI number: NPP1XP0BAA
- The Dual POTS plug-in card 751322/2 is made up of one Expandable POTS plug-in card (Model 751322) combined with one POTS add-on card (Model 751322/1). It isolates up to two POTS circuits and can only be used with any Teleline Isolator 3-, 5-, and 8-card shelves wired for 4-wire service. CLEI number: NPP1YR0BAA
- The Expandable POTS plug-in card (Model 751322) has a Complex Programmable Logic Device (CPLD) located on the Station side portion of the card. The CPLD generates all the clocks used on both the CO and Station sides. It also controls the Subscriber Line Interface Circuit (SLIC). The SLIC drives the telephone on the Station side and generates the ringing signal for the phone using a switched mode circuit
- The telephone line is driven using a transformer to provide good longitudinal balance and eliminate common mode noise on the line
- The Station side ringing generator provides a 20 Hz ring signal for North American networks
- The card’s specifications meet EIA/TIA 968 requirements. The CO circuit operates with line currents between 15 mA and 23 mA (the card limits current at 23 mA) allowing the card to operate on a line of up to 2,000 Ω (excluding card). The Station side SLIC will detect off-hook with currents as low as 16 mA and limits the phone current to 26 mA
- The audio signal is modulated and demodulated on both sides, in full duplex
- The CO side has a ringing detector that operates from a ring signal of 17 Hz as low as 40Vrms
The card can be housed in the 3-card shelf, the 5-card shelf, the 8-card shelf, or in any of our High Voltage Interface (HVI) pre-configured units.