LEYBOLD 230035V02, Руководство по эксплуатации

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25 300544652_002_C1 - 11/2016 - © Leybold
FAQ (Frequently Asked Questions)
Applications
Q:
Can the transmitter and sensor element continuously withstand vibrations from mechanical fore-pump?
A: Yes
– The MEMS sensor element can withstand continuous vibrations.
Q:
Is the transmitter compatible with fluorine gases?
A: No
– The transmitter is not intended for use in aggressive environments, like semiconductor etch applications.
However, the sensors coated with Parylene-HT® offer better resistance against various corrosive gases compared
to the standard MEMS Pirani. Refer to chapter 3.3.
Q: When the transmitter is pumped down and isolated by closing a valve the pressure is rising. Is the transmitter
leaking?
A:
Not likely - When a confined space is evacuated and the pumping is stopped the pressure will rise because of
outgassing mainly by water vapor. The pressure can easily rise to a few mbar over time.
Q: When the transmitter is leak checked on a helium leak detector. Leak reading is building up slowly after
approximately 30 seconds. Is the transmitter leaking?
A:
No - The internal sealing of the transmitter uses elastomer FPM sealing and consequently helium molecules can
penetrate though the FPM material and cause slow increase of helium leak readout. If a leaking transmitter is
tested directly on a helium leak detector the leak is almost instantly displayed.
Q: Can the transmitter be mounted in any orientation?
A: Yes - The transmitter can be mounted in any orientation without compromise of performance or calibration.
However, i
t’s recommended not to mount the transmitter with the flange port facing upwards to avoid
contamination, like particulates or liquids, from entering the device.
Q: Can the transmitter withstand instant ventilation?
A: Yes - The sensor element is extremely robust to mechanical forces and can withstand continuous pressure
cycles and instant air ventilation.
Q: Can I connect a valve to be controlled by the transmitter relay contact?
A: Driving inductive loads such as valves requires special precautions. Refer to chapter 4.2.
Q: How many pressure cycles can the transmitter withstand?
A: The sensor element is very robust to pressure changes and the number of pressure cycles will have no effect on
the lifetime of the transmitter.
Analog output
Q:
What is the update rate of the analog output?
A: 16 times per second.
Q: What is the maximum length of analog output cable?
A: The length of analog cable depends on cable quality and electrical noise environment, but a cable length up to
100 m do normally not require any special precautions other than cable must be screened.
Q: How long is the waiting time from turning power on to valid measuring values?
A: The power on sequence is approximately 2 seconds. The light ring is illuminating red during power up
sequence. Reliable measurements are typically available within 1 minute.
Calibration and adjustment
Q:
How often does the transmitter require calibration or Zero adjustment?
A: It depends on the application and pressure range. In many applications user adjustment is never required.
Factors that temporally or permanent can influence the measuring performance is contamination, corrosion, heat
and electronic interference.
Q: Will the transmitter retain user calibration after power is shut off?
A: Yes - All transmitter parameters including calibration data is stored internally in the transmitter nonvolatile
memory.