Avery Berkel CX20 SERIES, Руководство по обслуживанию

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23 — RS232 Interface PCB (CX20 W)
23–7 CX20/CX30/CX34 Service Manual
23.2.9 Serial interface devices
There are now a large number of devices that can that be connected to channel
B of the 82530 DUART on the main PCB. In a typical application not all devices
will be required. There are a number of invalid combinations of devices. In
addition to the ULMA wrapper the possible serial peripheral devices are:
DCU
Plugs into front of machine, detect link present within DCU. This device can be
used with the ULMA interface PCB, the RS232 interface PCB is temporarily
disabled.
Remote programming keyboard
This plugs into the front of the machine, detect link present within keyboard.
This device can be used with the ULMA interface PCB, the RS232 interface
PCB is temporarily disabled.
Remote operators keyboard
Plugs into front of machine, no detect link. This device cannot be used with the
ULMA interface PCB.
TK keyboard (internal or external versions)
The internal version plugs into a TK connector within the machine, this
connector is effectively in parallel with the DCU socket. The TK keyboard has
no detect link. This device cannot be used with the ULMA interface PCB.
External printer
This plugs into the new RS232 connector. If an ULMA wrapper is required with
an external printer, the ULMA now plugs into another RS232 channel built into
the remote printer.
23.3 Servicing
23.3.1 Replacing the RS232 interface PCB
To remove the RS232 PCB, proceed as follows:
1 Make back–up of unit data (refer to Part 2, Programming Handbook for
use of the DCU).
2 Switch off machine and isolate it from the mains power supply.
3 Remove case (refer to Section 3).
4 Remove main PCB, with display PCB and rear plate still attached (refer
to Section 11).
5 Disconnect all electrical connections from the RS232 interface PCB.
6 Remove the six screws with integral shakeproof washers securing the
RS232 interface PCB to the pillars in the base. If necessary, unscrew
and remove the plastic pillar protruding through the hole in the RS232
interface PCB. Lift out RS232 PCB.
7 Fit the RS232 interface PCB in the reverse order.