09-2018
file: ISAFE3-OperationManual_EN_DE.R4.VEXH.docx
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Vallen ISAFE3 Operation Manual - Operation Manual
IIC
Explosion group; for gases needing the lowest amount of energy
(< 60 µJ, hydrogen) to ignite an explosion.
Group IIC specification covers also IIB and IIA, since these groups are for
gases of higher ignition energy (60 to 180 µJ with IIB, e.g. for ethylene,
and > 180 µJ with IIA, e.g. for propane)
T6
Temperature class, defining the maximum surface temperature a gas can
reach in this apparatus stays always at least 5 K below 85 °C. T6 is the
temperature class of lowest temperatures and covers the requirements of
T1 - T5.
Ga
Equipment protection level (EPL) "Ga": Equipment for explosive gas
atmospheres, having a very high level of protection, which is not a source
of ignition in normal operation, expected malfunction, or when subject to
rare malfunction. Such equipment will have a form of protection which will
remain effective even in the presence of two potential faults or will have
two independent means of protection.
IP68
Degree of protection against ingress of dust and liquid.
First digit "6" means completely protected against ingress of dust.
Second digit "8" means suitable for continuous immersion in water under
conditions which shall be specified by the manufacturer.
Tamb: -20..+60°C
This is the range of ambient temperature this apparatus can be operated
in. For maintaining intrinsic safety, the upper limit is essential. The lower
limit has no influence on intrinsic safety and is a pure functional
specification.
7.2
Specifications ISAS3-xxx
7.2.1
Mechanical specifications
Protection class (EN60529)
IP68 (cable connected)
(for 12 bar peak pressure seal the cable-to-ISAS3-
transition according to specification
in chapter 8.3)
Ambient temperature
-20 °C
… +60 °C
Case material
Stainless steel 1.4571 (German: V4A)
Case isolation
None, case connected to shield and minus pole of
intrinsically safe circuit
Sealing
Three transitions (piezo-cup to base plate, base plate to
cylinder, connector-adapter to cylinder) laser-welded,
cover to cylinder sealed by threat and O-ring 1.78 mm
thickness, made of FKM
Sealing adapter
(for cable to ISAS3 sealing)
11.0 mm diameter, 14 mm width (for 11 mm wide clamp),
plus ridge with 11.5 mm diameter, 0.75 mm width. (See
Figure 7-2)
Earth connection
2 threads M4, see chapter 9.4 or 8.1
Maximum surface temperatures
(worst case fault)
T6: < 85 °C at 60 °C T
amb
