INFICON PSG55x ATM to Medium Vacuum Gauge - Manual (Page 38)

38 tina60e1-a (2011-04)
4.2 Gas Type Dependence
The measurement value is gas dependent. The pressure reading
applies to dry air, O
2
, CO and N
2
. For other gases, it has to be
corrected (→ "Technical Data").
If the gauge is operated with an INFICON controller, a calibration
factor for correction of the actual reading can be applied (→
of
the corresponding controller).
4.3 Switching Functions SP1, SP2
The two switching functions can be set to any pressure within
the measurement range of the gauge. A solid state relay is
provided for each switching function.
The current threshold setting
• can be read / written via the diagnostic port
• is output at the measurement signal output instead of the
pressure signal, can be measured with a voltmeter, and is
displayed on the LCD display after the <SP1> or <SP2>
button is pressed
• can be read / written via the DeviceNet, Profibus and RS485
interface.
Switching characteristics and hysteresis
The switching characteristics and the hysteresis of each set
point can be programmed (
→  41).
Low Trip Point
(default)
If the pressure in the vacuum system is lower than the setpoint,
the corresponding LED (<SP1> or <SP2>) is lit solid and the
corresponding relay is closed.