ELCOM Euro-500T Handy, Руководство по обслуживанию

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Euro-500T Handy © Elcom Ltd.
Service manual
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the cash register doesn’t work after it is switched on (disconnected network adapter)
damaged or unconnected main power switch - check the connection of the switch cable to the main PCB
(PWRSW connector)
- use the multimeter to check the functionality of the switch
(it is situated on the keyboard PCB)
damaged cable between the board of connectors
and the main PCB - use the multimeter to check the entirety of the second
conductor cable interconnecting the board of connectors
and the main PCB
- check the connection of the cable connector to the main
PCB (REAR 2 connector)
interrupted F1 fuse filament - check F1 fuse (3,15 A) - replace
discharged battery - check the voltage of the battery. If it is too low, charge it.
If the battery can’t be charged or if it loses the voltage too
quickly, replace the battery.
battery connected to the wrong connector - check if the battery is correctly connected to the main PCB
(BATT connector. Beware of the exchange with a cable
either of the main power switch or of the winding motor)
incorrect value of VCC voltage - check if the LVOFF/NMI signal reaches the level of 7,6 - 6 V
when the main power switch is switched on, consider the
battery condition (if it doesn’t, check U12, R5, R6, C8, C13,
D20)
- if the LVOFF/NMI signal functions properly, replace U14
- check if there is no cut-off towards GND in the whole
supplying passage of VCC voltage (damaged semi-
conductive component)
incorrect value of VRAM voltage - damaged D4 diode - replace
- check if there is no cut-off towards GND on the supplying
part of VRAM (damaged semiconductive component)
•
deleted RAM memory each time the cash register is switched on
faulty reserve NiCd battery - replace the NiCd battery (use the same type of the battery
only)
wrong position of JP1 jumper - the right position, during its operation, is closer to the NiCd
battery (the position further from the NiCd battery causes a
deletion of the memory)
•
the notice “Overheated head” appears on the display after the cash register is switched on
non-functional VCC1 power supply - use the oscilloscope to measure whether the SAVEPWR
appears when switching to log.1. If it does, measure or
replace R35, R29, T14, T15 (test 910).
•
the cash register doesn’t print (the motor shifts the paper ribbon)
non-functional VH power supply - use the oscilloscope to measure whether the SAVEPWR
appears when switching to log.1. If it does, measure or
replace T6-T9 and R20, 21, 22, 28 (test 910).
•
the cash register reports a fault in the fiscal memory (FM)
the fault is in one of the fiscal memory power supplies - check the output voltage of the secondary power supply
(use test 730), alternatively replace U 15
- check the output voltages of the FM power circuits
(or replace T3-T5, U16, D7, D18, R15-19)
6.2 Failures of micro-processing system
•
after the cash register is switched on, it doesn’t react, displays faulty characters, prints undefined
characters, whistles, and the back-light flickers
the voltage of the internal accumulator is too low
(disconnected adapter) - switch the cash register off, connect the network adapter
to the cash register and continue to work; recharge the
accumulator
- if the same happens after the accumulator has been
recharged, replace the battery or alternatively find the
cause of the permanent high power consumption from the
battery (the permanently switched-on back-light, a faulty
semiconductive component, etc.)
- examine the R56 and R57 divider