Vallen ISAFE3 Series, Руководство по эксплуатации

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09-2018 file: ISAFE3-OperationManual_EN_DE.R4.VEXH.docx 13 of 58
Vallen ISAFE3 Operation Manual - Operation Manual
Hence, SISO3 can be used with any AE signal processor providing a preamplifier supply
voltage of 28 V
DC
@
90 mA over a coaxial cable of 50 Ω impedance.
ISAFE3 supports automatic sensor coupling verification: An AE signal processor sends an AST-
control-pulse (short-cuts of 28 V supply voltage for some microseconds duration) to the signal
isolator SISO3, which sends a similar pulse to the sensor ISAS3. The ISAS3 uses the pulse to
generate an AE wave that propagates through or along the test object to be picked up by
neighboring sensors. Changes of the received amplitudes of different pulsing tests are an
indication for coupling problems with the sensors. The AST control pulse is supported by
Vallen's AE signal processor ASIP-2/A.
For optimum performance and signal-to-noise ratio, the signal processing chain inside the AE
system should comprise application specific frequency filters optimized for the application, e.g.
as provided by Vallen ASIP-2/A.
4.1 Members of ISAFE3 family
ISAFE3 product family consists of the following variants of the intrinsically safe piezoelectric AE-
sensor ISAS3-xxx, the signal isolator SISO3 and accessories.
Table 4-1 Members of ISAFE3 with ATEX type certification
Type Description Ex Protection
ISAS3-030 AE-Sensor for 25 to 80 kHz <EX> II 1G Ex ia IIC T6 Ga
ISAS3-075 AE-Sensor for 50 to 300 kHz <EX> II 1G Ex ia IIC T6 Ga
ISAS3-150 AE-Sensor for 150 to 450 kHz <EX> II 1G Ex ia IIC T6 Ga
ISAS3-150-V01 AE-Sensor for 150 to 450 kHz <EX> II 1G Ex ia IIC T6 Ga
ISAS3-375 AE-Sensor for 300 to 500 kHz <EX> II 1G Ex ia IIC T6 Ga
ISAS3-900 AE-Sensor for 100 to 900 kHz <EX> II 1G Ex ia IIC T6 Ga
SISO3 Signal Isolator (and barrier) <EX> II (1) 3G Ex nA [ia Ga] IIC T4 Gc
ISAS3 variants differ only in the geometry of the piezoelectric element and piezo-cup, hence in
the frequency response. Every ISAS3 contains a preamplifier with 20 dB gain.
SISO3 gain can be set to 14 dB, 20 dB or 26 dB by jumpers and can be changed by the user.
Default gain is 14 dB for a total gain of 34 dB (including 20 dB of ISAS3).
Table 4-2 ISAFE3-Accessories, no certification required
Type Description Chapter
HISO3-08 Housing for up to 8 SISO3, IP54 6.1
HISO3-20 Housing for up to 20 SISO3, IP54 6.2
MAG4IS Magnetic holder for all ISAS3 variants 8.1
SS-OIL-5MM Sealing Set Hardware for ISAS3 8.3.1