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ASM 421 Technical Description
6GT2 097-3AH00-0DA2
– 13 –
RD: 03/02
6GT2 002-0DA00
ASM 421 / V.24
Subject to change without notice!
6GT2 002-0DB00
ASM 421 / RS422
6GT2 002-0DC00
ASM 421 / TTY
J31069-D0142-U001-A0-7618
2.4.3
TTY cabling
TxD
RxD
max.
length
1000 m
+
+
TxD
RxD
ASM 421 (passive)
Computer (active)
b4
z4
b6
z6
X1
–SE
+SE
–EM
+EM
X2
1–9
SLG
b30/
z30
The ASM module does not contain any power sources for energizing the active part of the TTY interface.
Should, however, it become necessary for the ASM to power the interface, the ASM should be wired as
follows to make it active:
TxD
RxD
max.
length
1000 m
TxD
RxD
R
R
R
R
ASM 421 (active)
b4
z4
b6
z6
b32
z2
X1
Computer (passive)
X2
1–9
SLG
b30/
z30
The resistors R should each have a value of 470 Ohms to produce a current loop of 20 ... 30 mA
(P = 0.5 W).