General Monitors TS4000H, Instruction Manual, Page: 73 / 105

TS4000H
65
5.9.20 Sensor Scale (0x0018)
A read returns the current sensor scale. Sensor scale value is determined automatically by
sensor type, and cannot be written over Modbus. For a list of available sensor scales and
associated sensor types, refer to Table 34
Sensor Type Sensor ID Full Scale Value
0 No Sensor Detected None
1 O
2
25% v/v
2 CO – 100 100 ppm
3 CO – 500 500 ppm
4 Cl
2
– 10 10 ppm
5 ClO
2
3 ppm
6 HCl 20 ppm
7 NO 100 ppm
8 NO
2
20 ppm
9 NH
3
50 50 ppm
10 NH
3
100 100 ppm
11 Reserved N/A
12 SO
2
-20 20 ppm
13 SO
2
-100 100 ppm
14 H
2
S – 20 20 ppm
15 H
2
S-100 100 ppm
16 H
2
- 500 500 ppm
17-18 Reserved N/A
19 Cl
2
– 20 20 ppm
20 H
2
S – 50 50 ppm
Table 34: Sensor Scale
5.9.21 Sensor Type (0x0019)
A read returns the current sensor type. A write is allowed only if the current sensor is set to:

“0” (no sensor)

“9” or “10” (any SOOO2

“2” or “3” (any CO sensor)

“4” or “19” (any CL
2
sensor)

“12” or “13” (any NH
3
sensor)

“9” or “10” (any NH
3
sensor)
If the sensor type is set to:

“0”, only sensor type value of “1” can be written, defining O
2
sensor

“2” or “3”, only sensor type values of “2” and “3” can be written, defining CO – 100
ppm and CO – 500 ppm scale sensors, respectively
In all other cases, the sensor type is determined automatically when the sensor is plugged in.
Write attempts in such cases will return a data Exception Code 03 (Illegal Data Value).