@
064
40
‘
096
60
A
065
41
a
097
61
B
066
42
b
098
62
C
067
43
c
099
63
D
068
44
d
100
64
E
069
45
e
101
65
F
070
46
f
102
66
G
071
47
g
103
67
H
072
48
h
104
68
I
073
49
i
105
69
J
074
4A
j
106
6A
K
075
4B
k
107
6B
L
076
4C
l
108
6C
M
077
4D
m
109
6D
N
078
4E
n
110
6E
O
079
4F
o
111
6F
P
080
50
p
112
70
Q
081
51
q
113
71
R
082
52
r
114
72
S
083
53
s
115
73
T
084
54
t
116
74
U
085
55
u
117
75
V
086
56
v
118
76
W
087
57
w
119
77
X
088
58
x
120
78
Y
089
59
y
121
79
Z
090
5A
z
122
7A
[
091
5B
{
123
7B
\
092
5C
|
124
7C
]
093
5D
}
125
7D
^^
094
5E
~
126
7E
_
095
5F
DEL
127
7F
Modbus communications
This addendum covers the use of Modbus RTU communications when using the LD4 monitor.
When using Modbus communications the instrument must be set up electrically for RS232 or
RS485 communications and the
O.Put
function must be set to
M.bus
.
Modbus commands
Note:
the maximum recommended baud rate is 9600.
The following commands are available:
Function 1 Read coil status
Reads the ON/OFF status of the relay coils. Broadcast is not supported. Relays 1 to 4 are addressed
as 0 to 3. Logic 1 = ON, Logic 0 = OFF.
To read the coil status a query is sent to the LD4, the LD4 then responds to the query.
Page 42 of 46
LD4LNMAN-1.0-1
