Manual / Guide
Installation of No. 755A PBX Lamp Circuits (addendum to 550-550-210) — AT&T BSP 550-550-210 Addendum
2 pp. The only 755A BSP in TCI's 550 folder that the Library lacked
Manual / Guide
2 pp. The only 755A BSP in TCI's 550 folder that the Library lacked
SYSTEM PRACTICES Series ADDENDUM 550-550-210 PA~ Issue A, November, 1963 BoT. Co. of: Pa .. Philadelphia Area Installation of No.755A P.B.X. 71; ::e Lamp Circuits 1. GENERAL This Addendum supplements the main section. It is~ issued to add the wiring changes as per drawing ll-M-15. 1.10 Western Electric Company will add a L6A Terminal Strip and wiring, also relays for control of trunk lamp circuits. Power for all trunk lamps at all stations is 10 volts A.C. use 5lA lamps for all trunk lamps. 3.. PREPARATION Source of Power 3.27 If KoSo=5538 9 List 6 storage batteries are used for P.B.X .. power g the 393B transformer should be the source of lamp power as per drawing ll-M-l5 o 3.28 If P.B.X. is located where a reserve power supply is not required in the event of commercial power failure. the Lorain Power Plant Model RT2B or T2B should be used for both P.B.X. and Lamp Supply Power" 3.29 All wiring between Power Plant Supply and P.B.X. Cabinet sadl be 20 Gauge AM wire. Installation 3.30 200 Pairs of inside wiring cable are required between PoBoX. cabinet and distributing terminal to bring lamp features from PoBoX. 3.31 Table A of main section (Page 16). Lamp leads terminating, on cable pairs 151-200 shall be disregarded and terminated as per drawing 11-M-l5 in the P.B.X. . Strap ACI and AC2 at P.B.X~ cabinet terminml when using 10 volt 9 10 ampere A.C. lamp supply from the Lorain Type Power Plant. 3.32 ADDENDUM 550-$5Q~210 PA a~33 Disregard 3.34 The ll-M-15 print is included with 755A P,B.X. Page 2 figu~es 6. 7, 8. 9 and Table B of main section. drawi~g.