ZETRON Model 25, Руководство по эксплуатации продукта, Страница: 41 / 147

Encoder Installation
025-9567E 33
Serial Port Control
The serial port of the encoder is used to communicate with devices attached to the computer
port or the instant call panels depending on the state of the “RMT-CTL” signal. A problem in
the wiring of either the auxiliary panels or remote control devices may result in a non-
functional encoder. As a fault isolation aid, the serial port may be disabled from transmitting
or receiving characters. When disabled the encoder will function normally from the keypad
only. Note that two seconds or more of a “break” or “space” level at the computer port will
always result in the encoder being reset.
The serial port is enabled or disabled via the encoder keypad by holding down the
RESET
key then holding down the “1” key and releasing the
RESET
key. When the encoder shows
the word “
PrOG
” the “1” key may be released at which time the display will change to
“
1__
”. To enable the serial port, key-in the number “61”. To disable the serial port, key-in
the number “60”. After keying the two-digit number, the encoder will return to the normal
idle state.
The serial port should not be disabled from a PC since remote control of the encoder will be
lost when the serial port becomes disabled. Enabling of the serial port from a PC is pointless
since it must be enabled for the PC to command the encoder. Removing and reapplying the
power to the encoder will cause the serial port to be enabled.
DISASSEMBLY AND CIRCUIT LOCATION
In order to change any of the factory settings, the encoder will need to be opened up. Figure 6
shows a disassembly view of the encoder. Refer to this diagram to find the location of the
various circuit boards in the encoder. To open the encoder, loosen two of the screws that
retain the top cover near the front panel. Loosen two of the screws that retain the bottom
cover near the back panel. Remove the two remaining screws that are retaining the top cover
near the back panel. The top cover may now be removed and the back panel (holding the
encoder board) may be hinged down. When replacing the top cover, be sure that the turned-
down lip faces the front panel otherwise the front panel may flex if pressed excessively.