Cascade Sciences CVO-5-EX Series, Руководство по установке и эксплуатации

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INTRODUCTION
E
XPLOSION
P
REVENTION
S
YSTEMS
O
VERVIEW
The oven incorporates features designed to reduce the potential for the ignition of flammable or
combustible gases in the previously specified hazardous location types. These systems do not
eliminate the risk and do not reduce the requirements for operators competent to work in
hazardous locations or adherence to hazardous location standards or directives.
• Chamber Build: The oven chamber is a sealable environment containing no electronic
components and does not allow outgassed gases or vapors access to components elsewhere in
the oven.
•
Door Window:
The oven door window is a blast-safe safety window to protect against
implosions due to vacuum in the oven chamber.
•
Purge and Pressurize System (Ex pzc)
: The oven electronics and heating elements are
situated in internal enclosures. These connected enclosures are automatically purged and over-
pressurized with a safe gas before the oven’s high voltage components can be powered. The
over-pressurized enclosures automatically seal when the oven is turned on by the oven operator.
•
IS and Encapsulated Components (Ex ia mc ) : Only Intrinsically Safe components and
circuits and encapsulated components are powered in the electronics enclosure before the
completion of the purge and over-pressurization process.
• Overpressure: The electronics and heating element enclosures maintain an overpressure after
the purge to prevent potential intrusions of explosive gases or vapors.
•
Safety Interlocks:
o
The oven's high-voltage components (electronic controls, display, and heating elements)
automatically depower if the connected electronics and element enclosures lose over-
pressurization.
o High-voltage components and oven heating can only be turned back on after an
overpressure loss once the oven has purged and pressurized the enclosures again.
o The oven chamber will only heat when under vacuum. The oven automatically depowers
the heating elements if vacuum is lost in the chamber.
o
An internal gas regulator helps prevent excessive over-pressurization of the internal
enclosures that could damage the oven. The oven is also equipped with a pressure relief
valve in the event the enclosures become excessively over-pressurized.