Oki ML421 Maintenance Manual
Also see for ML420 Series: Specification sheetUser guideUser guideInstallationInstallation
                                                                                                                                     | |
Contents
| 
42113901 Rev.2 27 /Oki Data CONFIDENTIAL50VR542R541POWLEVVoltage, 50V Pass number Print speed38V or more 1 Pass 100%25V to 37V 1 Pass 100~30%25V or less 1 Pass 30%2.1.8 Alarm Circuit(1) AC fuse open alarm(a) Head drive time alarm circuitThis circuit monitors the drive time using the HDALM signal interlocked with theoverdrive signal of each drive circuit.If the drive time of any drive circuit exceeds the specified time, the drive fault alarmcircuit sends an ALM-N signal to turn on the Thyristor.This cause the secondary coil (50V) of the transformer to be short-circuited, causingan overcurrent to flow through the primary coil and making the AC fuse (transformerassy) open.(b) Overvoltage detection50V, 12V and 5V voltages are monitored, at overvoltage alarm circuit turn-on, the ALM-N signal is transmitted to the thyristor, then the AC fuse (transformer assy) opens.(2) Alarm processing when DC power is low.50V is converted into the POWLEV signal (0V to 5V) by R542 and R541 and input intothe A/D port of the MPU to control the drive time and the print speed (pass number) ofthe head.(a) Head drive timeThe head drive time is lengthened to compensate for the amount of voltage drop bymonitoring the POWLEV signal once every 500 μ sec. to control and maintain theimpact necessary for each printing pin at the fixed value.(b) Print speed(3) FAN alarmThe MPU detects 5V on the FANALM signal even through the fan is driven.5VR512FANALM-P |
Related manuals for Oki ML420 Series
This manual is suitable for:
manualsdatabase
Your AI-powered manual search engine