CSZ ZP 16, Installation, Operation & Maintenance Manual, Page: 27 / 88

GENERAL DESCRIPTION
Page 2-11
Some options may be equipped with a GFCI Receptacle for power. If any options
are installed in this manner, check the GCFI Receptacle(s) monthly.
PEN RECORDERS (OPTIONAL)
The Circular Chart Recorder features fully programmable inputs ranging and
linearization with stepper motor pen and chart drive speed. This eliminates the need
for range cards and chart speed change gears. Con
fi guration is fi eld programmable
for fl exibility to meet changing test requirements. Refer to the chart recorder manual
on the digital media, or supplemental booklet, if applicable.
Replacement chart paper is available from the CSZ Service Department.
REDUNDANT HIGH/LOW LIMIT CONTROL (OPTIONAL)
The High/Low Limit Control is designed with set-points for high and low
temperatures. These can be precisely set at temperatures to permit safe operation.
The Limit Control will shut down the chamber operation and product operation if
the safe operating temperature limit of the product, either hot or cold, has been
exceeded.
IEEE-488 SYSTEM (OPTIONAL)
An optional IEEE communication interface can be provided on the chamber to allow
the EZT-570S to communicator over the GPIB bus.
LN2/CO2 BOOST COOLING SYSTEM (OPTIONAL)
In addition to the main refrigeration system, the chamber is equipped with an
optional connection port for supplying boost cooling from an external source of
cryogenic lique
fi ed gas (either carbon dioxide or liquid nitrogen). The boost cooling
gas is vented directly into the chamber by a controller under the conditions of
sustained cooling demand.
Refer to the System Diagrams Chapter to see the schematic diagram for the boost
cooling system when using LN2 as the boost cooling agent.
LN2 can be supplied in one of two ways, either by an LN2 Cylinder or with a central
supply using vacuum jacketed lines.
When using an LN2 Cylinder, it must be connected with a well insulated line that is at
least 3/8” inside diameter. The line length should be 5FT (152 cm) or less. The LN2
tank should have a maximum supply pressure of 25 PSIG (274 kPa) and be able to
provide 0.60 gallons/min.
With a central supply using vacuum jacketed lines, there is no maximum line length.
Mode
Mechanical cooling with LN2 boost:
At temperatures above -70°C the refrigeration system operates normally. When the
LN2 switch is turned “on” the LN2 cooling valve will open when there has been a call
for cooling from the controller for more than 10 seconds. This will boost the cooling
effect and reduce the temperature in the chamber faster.
The vent duct connected to top of the chamber to exhaust the gaseous nitrogen
should be well insulated and 10 FT or less. If over 10 FT, the duct size will have to
be increased. Contact CSZ for sizing.
The redundant high/low limit
has a red LED display which
displays a “SAFE” condition
when temperature has
returned to safe conditions,
press the “RESET” button to
reset the limit.
NOTE
!
Gaseous Nitrogen/CO2 vent
must be ducted out doors.
To prevent displacement
of oxygen around the unit.
Asphyxia can occur if this is
not installed properly.
WARNING
!
Wear appropriate PPE
when handling LN2
connections.
WARNING
!
I f a n y o p t i o n s a r e
installed using a GFCI
Receptacle, check the
GCFI Receptacles(s)
monthly.
CAUTION
!