Oldham iTrans

iTrans Fixed Point Single/Dual Gas Monitor ModBus Interface
(P/N: 77023554-1) iTrans User Manual 6-3
Addr
Inst
R/W
Host
R/W
Range
Description
40103
R*
R*
MSB = $01 to $FF
LSB = $01 to $FF
Gas Type
Holds the decimal place holder and the gas type
code. The most significant byte (MSB) holds
the number of decimal places to be used in
calculations for this gas. This decimal locator
applies to all subsequent values of gas readings
within other registers. This can be read by the
instrument. The least significant byte (LSB)
holds a code which identifies the gas type.
This can be read by the host.
MSB = Decimal place holder $01 to $FF
LSB = Gas type code $01 to $FF
$01 CO Carbon Monoxide
$02 H
2
S Hydrogen Sulfide
$03 SO
2
Sulfur Dioxide
$04 NO
2
Nitrogen Dioxide
$05 Cl
2
Chlorine
$06 ClO
2
Chlorine Dioxide
$07 HCN Hydrogen Cyanide
$08 PH
3
Phosphine
$09 H
2
Hydrogen
$0C NO Nitric Oxide
$0D NH
3
Ammonia
$0E HCl Hydrogen Chloride
$14 O
2
Oxygen
$15 CH
4
Methane
$16 LEL Lower Explosive Limit
(Combustible Gases)
Examples:
$0107 = 1 decimal place for gas type HCN
$0002 = 0 decimal places for gas type H
2
S
$0206 = 2 decimal places for ClO
2