INFICON BCG450-SP ATM to Ultra-High Vacuum Triple Gauge (Profibus) - Manual (Page 35)

tira41e1 (2005-06) BCG450SPv1.cp
35
Atmospheric pressure
× N
Atmospheric pressure threshold = —————————————
100
Where:
Atmospheric pres-
sure threshold [mbar] : If the pressure inside the vacuum chamber rises
above this threshold, the relay "Atmosheric pres-
sure reached" is energized.
Atmospheric
pressure [mbar] : Atmospheric pressure (100%, ambient)
1)
N [%] : "Percentage of Atmosphere"
(1 … 140%, default value = 5%)
(Example values in the diagram below are printed in italic)
M
ea
su
re
d
va
lue
Measuring signal
(Pressure p)
833 mbar
816 mbar
1500 mbar
980 mbar
Atmospheric pressure (100%, ambient)
"Percentage of Atmosphere"
(85%)
(Atmospheric pressure
threshold)
Hysteresis
(2% of atmospheric
pressure threshold)
Relay status "Atmospheric pressure reached"
Upper limit of measuring range of gauge
1)
1)
The (piezo) sensor measuring atmospheric pressure can be calibra-
ted to the value of the Capacitance Diaphragm Gauge pressure
(
→ 41).
The value "Percentage of Atmosphere" has to be entered as follows:
N' = 10 × N
Where: N = "Percentage of Atmosphere", as described above
N' = Value to be entered in ID202
(range 10 … 1400
1 … 140%)
Example: For a "Percentage of Atmosphere" of 50(%) enter 500 in ID202.
Setpoint function
"
Atmosphere Control"
ID202 value