R1
R2
P2
P1
Span Adj.
Made in EU
Zero Adj.
R3
R4
Made in EU
F1
Buss
400mA
R2
P2 Span Adj.
R1
P1
Zero Adj.
R3
R4
Exc
6
7
Gnd
Gnd
Gnd
9
Pwr
Out
In
Out
In
Tx
Tx
Rx
Rx
+
+
0
1
-
-
0
1
8
Sen
5
Inp
4
Inp
3
Sen
2
Exc
1
0
16
17
19
18
15
14
13
12
11
10
+
+
+
-
-
-
I I I
Load Cell Digitising Unit
LDU 68.1
Cert.no. DK0199 - R76 - 10.04
n
max
= 10000
-15°C/+55°C
CE
D
min = 1.0
m
V/VSI
NC
NC
TECHNIQUES LIMITED
www.sensortechniques.com
Connect the
Signal Ground
to the Power
Supply Ground
Connect the
Signal Ground
to the Power
Supply Ground
Ideas in Measuring ..
TECHNIQUES LIMITED
Page 40
LDU 68 Series Manual
The following example shows how to wire up 2 or more LDU 68.xs in a multi-drop application to an
USB port of a PC using a USB to RS422/485 converter. This circuit has been tested and is known
to work correctly. The USB to RS422/485 converters can be purchased from Sensor Techniques
Limited
10 USB to RS422/485 CONVERTER WIRING (MULTI-DROP)
Issue 1h
1
5
6
9
Tx +
Rx +
Rx -
Screen
Tx -
To USB
Port on
Computer
R1
R2
P2
P1
Span Adj.
Made in EU
Zero Adj.
R3
R4
Made in EU
F1
Buss
400mA
R2
P2 Span Adj.
R1
P1
Zero Adj.
R3
R4
Exc
6
7
Gnd
Gnd
Gnd
9
Pwr
Out
In
Out
In
Tx
Tx
Rx
Rx
+
+
0
1
-
-
0
1
8
Sen
5
Inp
4
Inp
3
Sen
2
Exc
1
0
16
17
19
18
15
14
13
12
11
10
+
+
+
-
-
-
I I I
Load Cell Digitising Unit
LDU 68.1
Cert.no. DK0199 - R76 - 10.04
n
max
= 10000
-15°C/+55°C
CE
D
min = 1.0
m
V/VSI
NC
NC
TECHNIQUES LIMITED
www.sensortechniques.com
REAR VIEW OF 9 WAY FEMALE D TYPE
CONNECTOR (SOLDER BUCKET)
