Xerox WorkCentre XK50cx Service Manual

Also see for WorkCentre XK50cx: User guide

4-17Circuit• +22V Power ControllerInsert the power cord, then power is supplied toMAIN BOARD through DRIVER PBA CN15./POR signal which is output through Reset Circutactivate the MAIN CONTROLLER and approve/F_POP signal which is output through MAINPBA(U9-1) and VREFX(+2.5V) to input terminal(U30-4,11)of comparison instrument.When the comparison output(U30:1) is " HIGH",the output is +22V, when the comparison output is"LOW", it will be "OFF".(/FAULT_TEST SIGN :HIGH) Also, after /F_POR is finished, during the+22V is permitting, when you input(U30-9)/FAULT_TEST sign as "LOW", the output(U30-1) ofcomparison instrument become "LOW" and makethe +22V TR(Q14,TIP112) OFF.• FAULT TEST CIRCUITThis is a signal to detect whether the headreceiving the output of head column driver is in ashort. After /FAULT-TEST signal is put out at “low”and +22V is turned “off”, “OK2PRINT” signal isentered. The port of KS32C6400 MAIN PBA(U15)shows normal condition if “H” and a short if “L”. Ifyou make FAULT-TEST output “L” to detect fault ofthe head, +22V gets off. If the head is in a short(LOW), when the level of “/FAULT-TEST” signalgoes “L” and final “OK2PRINT” output goes “L”.KS32C6400 MAIN PBA (U15) reads this signal andchecks whether the head input receiving thedriver output is in a short. Diode cathode isattached to each output transistor collector in thecolumn driver. 8 anode terminals of diode becomecommon as one and put out /FAULT signal, whichis pulled up by bias circuit controlled by /FAULT-TEST and shows the condition by OK2PRINTthrough the comparator.• SUBSTRATE HEAT CIRCUITMono ink cartridge of Babbage head is 600dpihead that uses pigment ink. It is very sensitive tothe temperature in and around the cartridge. Inparticular, the viscosity of ink affects print quality asit is inversely proportional to temperature by anexponential function. This signal used tocompensate it helps you get equal inking quality bywarming the ink chamber in the cartridge withaluminum pattern heater before starting to print ifthe surrounding temperature is lower thanstandard (below 35°…).(Refer to Timing Chart.) Itsends PRE-HEAT signal through I/O port ofDUOIP2(Color Image Main PBA:U16) and supplies+12V.Mono HeadFig.4-2-2 Temperature around Mono Head70°C35°CPre-Heat if below 35°c