LEYBOLD 230070V02, Руководство по эксплуатации

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18 300544652_002_C1 - 11/2016 - © Leybold
Operations
5.1
Pressure output
The PTR 90 N PENNINGVAC transmitter can provide pressure measurement output as an analog voltage or
RS232 digital value (P/N: 230088V02) or EtherCAT digital value (P/N: 230089V02). For details about the digital
interface, please refer to the Communication Protocol 300544663 (RS232) and 300544664 (EtherCAT).
The default analog output is based on the MEMS Pirani and cold cathode combined reading and provides a 16 bit
voltage output of 0.6 VDC/decade standard configurations. Refer to chapter 5.3 for details.
The MEMS Pirani automatically turns on the cold cathode at 6.7E-4 mbar (SLC) and turns it off at 1.1E-3 mbar
(SHC). Above 5.3E-4 mbar, the combined reading is the MEMS Pirani pressure measurement and below 1.3E-4
mbar it is the cold cathode pressure measurement. Between 1.3E-4 and 5.3E-4 mbar, the two measurements are
smoothly integrated.
SLC: Low CC turn on pressure (6. 7E-4 mbar)
SHC: High CC turn off pressure (1.1E-3 mbar)
SLP: Low CC/MP integration (1.3E-4 mbar
SHP: High CC/MP integration (5.3E-4 mbar)
In some application it is preferred not to have the (high voltage) turned on during vacuum process or during mass
spectrometer analyzing. The PTR 90 N PENNINGVAC cold cathode turn on pressure (SLC) and turn off pressure
(SHC) can be changed by the user. Furthermore, the high and low integration levels between the cold cathode
reading and MEMS Pirani reading can be changed by the user (see the communication protocol).
When designing external pressure control loops make sure that external equipment like pumping
system is not damaged if the transmitter output enters Sensor defect mode or in case of power
failure.
When designing pressure data collecting software and controlling loop make sure that the software
does not interpret a communication error as a valid pressure value.
Caution
Caution
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