80224_MHW_650 L - 1250 L_07-2018_ENG - 22
2.5. RS485 serial connection diagram
Up to 31 instruments (including different models) can be connected in parallel on the RS485 line. The line must end with a
resistor (120 Ω, 1/2 W).
4
3
2
1
9
10
11
12
21
22
23
24
4
3
2
1
9
10
11
12
21
22
23
24
Host computer
RS485
Shield
120 Ω
1/2 W
120 Ω
+
-
+
Earth ground (FG)
-
+
-
650
No. 1
650
No. 31
Figure 10 - RS485 connection for 650 L indicators
4
3
2
1
45
46
47
48
28
27
26
25
4
3
2
1
45
46
47
48
28
27
26
25
Host computer
RS485
Shield
120 Ω
1/2 W
120 Ω
+
-
+
Earth ground (FG)
-
+
-
No. 1
1250
1250
No. 31
Figure 11 - RS485 connection for 1250 L indicators
2. INSTALLATION