Instruction Manual
17
Troubleshooting
Problem Cause Action
The power indicator (POWER) 
does not light up.
Power is not 
supplied.
Make sure that the voltage of the power supplied to the 
sensor amplifier main unit is 20 to 30 VDC.
DL-RS1A is not 
properly inserted to 
the expansion 
connector of the 
sensor amplifier.
Reconnect the unit following the instructions in "Connecting 
the Unit to Sensor Amplifiers" (page 3).
The alarm indicator lights up 
before communication starts.
DL-RS1A is 
connected to a 
sensor amplifier that 
does not support DL-
RS1A.
Make sure that the unit is connected to an appropriate 
sensor amplifier model (refer to "Available sensor amplifiers" 
(page 4)).Reconnect the unit following the instructions in 
"Connecting the Unit to Sensor Amplifiers" (page 3).
The communication status 
indicator (RD) of DL-RS1A does 
not flash when you send a 
command from an external 
device.
The RD terminal of 
DL-RS1A is not 
connected to the 
SD terminal of the 
external device.
Check the connection wiring by referring to "Connecting the 
Unit to External Devices" (page 5).
No communication 
data is sent from the 
external device.
Make sure that communication commands are sent out from 
the external device.
The alarm indicator lights up 
while data is transmitted.
Communication 
settings are 
incorrect.
Make sure that DL-RS1A and the external device have the 
same settings specified for communication speed, data bit 
length, and parity check.
For information on configuring DL-RS1A, refer to "Part 
Names and Functions" (page 2).
The communication status 
indicator (RD) of DL-RS1A 
flashes but the communication 
status indicator (SD) does not 
flash while data is transmitted.
The communication status 
indicator (SD) of DL-RS1A 
flashes while data is 
transmitted, but the data cannot 
be retrieved by an external 
device.
Proper 
communication is 
not established.
Lower the communication speed. Use a shielded cable for 
the communication cable (refer to "Connecting the Unit to 
External Devices" (page 5)). Modify the connection wiring so 
that noise does not enter the communication cable.
A communication error 
response is returned from DL-
RS1A while data is transmitted.
For the cause and action, refer to page 13.
ASCII Code Table
The following table lists the ASCII codes.
0
0
1
2
3
4
5
6
7
8
9
A
B
C
D
E
F
123456789
S
P
N
U
L
D
L
E
D
C
1
D
C
2
D
C
3
D
C
4
N
A
K
S
Y
N
E
T
B
C
A
N
S
U
B
E
S
C
S
O
H
S
T
X
E
T
X
E
O
T
E
N
Q
A
C
K
B
E
L
B
S
E
M
H
T
L
F
V
T
F
F
C
R
S
O
D
E
L
S
I
0 @ P ` p
High-order 4 bits
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” 2BRb r
# 3CScs
$ 4DTd t
% 5EUeu
& 6FVf v
’ 7
Low-order 4 bits
GWg w
( 8HXhx
) 9IYiy
: JZ j z
+; K [ k {
,< L\ l|
ー=M ] m }
.> N ^ n
~
/
→
←
↑
↓ ?O_ o










