Appendix
OxyDetect Oxygen Deficiency Gas Detector
74
05311001B / Revision 4
A3.12 Transducer set-up mapping
Each transducer will provide read-write access to various set-up data in blocks of
holding registers that can be read with function code 03 and written with function
codes 06 and 16.
Each register provides 2 bytes of data so it takes 2 registers each to store a 4 byte
floating point measurement value.
A block of 100 registers is allocated for each transducer to provide the means of
supplying the transducer related set-up data as follows:
Register
Name
Comments
101 – 200
Transducer 1
Transducer 1 related data.
The following table shows the assignment for transducer 1. Each register provides
2 bytes of data.
Register
Name
Comments
Analogue Output
101 – 102
Range 1 low
Float.
103 – 104
Range 1 high
Float.
105 – 106
Range 2 low
Float.
107 – 108
Range 2 high
Float.
109
Range mode
0 = range 1, 1 = range 2,
2 = auto range
.
110
Freeze
0 = Follow, 1 = Freeze.
111
Jam
0 = None, 1 = low, 2 = high.
112
Output range
0 = 0 – 20 mA,
(0 – 10 V)
, 1 = 4 – 20 mA.
113 – 114
Under range
Float.
Calibration
121 – 122
Low target
Float. Also calibration target.
123 – 124
Low tolerance
Float.
125 – 126
High target
Float. Also calibration target.
127 – 128
High tolerance
Float.
Alarm set up
145
Alarm 1 mode
0 = none, 1 = low, 2 = high.
146
Alarm 1 latching
0 = no, 1 = yes.
