Communication solutions for power utilities
1U SHELF TYPE MAS-2
WITH ASYNCHRONOUS PROGRAMMABLE MODEM MAFP - Rev. 9 (January 2018)
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4.2
INTERNAL MICROSWITCH (MI2)
The modem has an internal microswitch (MI2) which allows its transmission speed and
central working frequency to be programmed, as well as the general alarm relay to be
blocked. Figure 21 shows the position of the microswitch in the card.
Microswitch 1:
Must always be in ON position.
Microswitch 2:
Blocking of the alarm relay.
ON:
Alarm relay blocked.
OFF:
Normal operation of the alarm relay
(controlled by CD signal).
Microswitches 3, 4 and 5:
Selection of the speed the modem will work at.
Microswitch
Transmission speed
(Bd)
3
4
5
ON
OFF
OFF
50
ON
OFF
OFF
75 (T
x
V.23)
OFF
ON
OFF
100
ON
ON
OFF
200
OFF
OFF
ON
600
OFF
OFF
ON
600 (T
x
V.23)
ON
OFF
ON
1200
ON
OFF
ON
1200 (T
x
V.23)
OFF
ON
ON
2400
Table 4 Programming of the transmission speed of the modem
Microswitches 6, 7, 8, 9 and 10:
Selection of the central frequency at which the
modem will work. Table 5 shows the arrangements
that must be carried out in microswitches 6, 7, 8, 9
and 10 in order to program the desired frequency (in
Hz), according to the speed programmed in
microswitches 3, 4 and 5.