LX Series Unit Ventilator Controller User's Guide
104
SNVT_ppm (29)
SNVT_switch (95)
Switch Definition
A structure reporting a percentage level or load value and a discrete on/off state.
Separate fields report the percentage value and state. You can use this type for both
discrete (on/off) and analog control.
You can use the value field to control the load’s value (position, speed, or
intensity). Use the state field to control whether the load is on or off (enabled or
disabled).
When you use the state field as the output of a discrete sensor device, the OFF state
is represented by a SNVT_switch network variable with state = FALSE and
value = 0. The other discrete states are represented by state = TRUE and value > 0.
When used as the output of a two-state sensor device, the ON state is represented
by state = TRUE and value = 200 (meaning 100%).
When you use as the input of a two-state discrete actuator, a SNVT_switch
network variable with state = TRUE are interpreted as the ON state if value > 0,
and as the OFF state if value = 0. In addition, a SNVT_switch input network
variable with state = FALSE should be interpreted as the OFF state, whether or not
value = 0. A state value of 0xFF indicates the switch value is undefined.
Table 46: SNVT_ppm
SNVT_ppm
Description
SNVT Index
29
Measurement
Concentration
Field Type Category
Unsigned Long
Type Size
2 bytes
Valid Type Range
0-65,535
Type Resolution
1
Units
Parts per million
Invalid Value
N/A (ppm)
Raw Range
0-65,535
(0-0xFFFF)
Scale Factor
1, 0, 0
S=a*10
b
* (R+c)
File Name
N/A
Default Value
N/A
Table 47: SNVT_switch
SNVT_switch
Description
SNVT Index
95
Measurement
Switch
Field Type Category
Structure
Type Size
2 bytes