Xerox WorkCentre Pro 423 Service Manual

Also see for WorkCentre Pro 423: Scanner guide Fax guide Brochure & specs Fax guide User guide

03/02 Level 2 TroubleshootingWorkCentre Pro 423/428 2-101 CHAPTER 2 TROUBLESHOOTING2.3.2.6 ISDN Fax installation notesISDN supports G4 and G3 fax communication. A G4/G3 Fax can accommodate an ISDN linedirectly but a G3 Fax cannot. Therefore, a G3 Fax is connected to ISDN through a terminaladapter (hereinafter, TA) or ISDN router (hereinafter, router). If the TA or router has an S/Tpoint (see "Explanations of terms"), a G4/G3 Fax may be connected directly there.G3 Fax communication through an ISDN line is called ISDN-G3.The following sections explain common terms about fax communication (G4 and G3) throughan ISDN line, fax and TA/router parameter setting notes, and troubleshooting in transmissionand reception.Explanations of termsl Terminating resistor (terminator)l ISDN cable, 10BASE-T cable, and modular jack (MJ) RJ45 and RJ11l S/T pointl Bus wiringInstallation notesl Several terminals on a single ISDN line (Bus connection)l Dial-in contract linel Using NET1500l PBX accommodationl G4/G3 Fax connection to S/T point of TA or routerl G3 Fax connection to analog point of TA or router2.3.2.7 Explanations of common termsl TerminatorNET64 requires two pieces of 100-ohm terminator on the farthest terminal (connection block).The terminators stabilize signals on a line. Without the terminators, errors will occurespecially when the DSU-terminal line is long or several terminals are connected by buswiring. Each line requires a pair of terminators.* An ISDN line uses a four-core cable consisting of two pairs of paired wires for TA/TB (signaltransmission) and RA/RB (signal reception). The terminators are connected between TA andTB and between RA and RB.TAs or routers and ISDN terminals may have built-in terminators that are turned OFF and ONby switches. If several terminals are connected by bus wiring, check the built-in terminatorsand leave the rsistors alive only in one unit (one pair). If several pairs of terminators are aliveon a line, the combined resistance goes down and may cause errors or other functionalproblems.l ISDN cable, 10BASE-T cable, and modular jack (MJ) RJ45 and RJ11A modular jack for an ISDN line is called RJ45. This MJ has eight pins for four wires.Although there are eight pins, only the four pins (pins. 3 to 6) at the centre are used. Thepolarities are TA (pin 3), RA (pin 4), RB (pin 5), and TB (pin 6). Paired-wire (stranded) cablesare used for wiring from DSU to MJ and between MJs. If a non-stranded cable is used for along distance, errors will occur.For terminal-side wiring, note the distance from DSU. The wiring forms are point-pointconnection where only one connection block or terminal is connected to a block and buswiring where several connection blocks or terminals are connected. The maximum distancesfrom DSU to the farthest terminal in the forms are as follows:Point-point connection: 750 mShort-distance bus connection (terminals at random intervals on a bus): 150 mLong-distance bus connection (all terminals centralized within 50 m on a bus): 550 mRJ45 MJ is connected to a terminal through a four-core ISDN cable. An ISDN cable has thesame MJ (MJ45) as a 10BASE-T cable for LAN. However, the cables are not compatible witheach other because their pin numbers and combinations are different from each other (seethe table below). If a 10BASE-T cable for ISDN is used, errors will occur.cable type Paired pin numberISDN Pin 3-6, pin 4-510BASE-T Pin 1-2, pin 3-6If communication errors occur in Fax communication, check the cable continuity, all thepolarities between DSU and connection blocks, and paired wires of the cable. Checking thepaired wires may make it necessary to unsheathe the cable partially.A small MJ for an analogue line is called RJ11. This MJ has six pins for two wires.Pin 8 … 16RJ45Connection block