Cosa 9610, Инструкция по установке, эксплуатации и обслуживанию

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INSTALLATION, OPERATION AND MAINTENANCE MANUAL – COSA 9610™
Page 15 of 48
Fixed Purge Time
If the purge time must be held to a specific time, then this time is based on the known
enclosure volume, number of volume exchanges, and flow rate through the vent. If the flow
rate is below the required minimum, then the purging cycle will reset and will not start until
the flow rate is above the selected rate. This set up does not allow purge flow to go below
the value required and will not recalculate the time for purging if it goes above the required
purge rate.
Dynamic Purge Time
Dynamic purge time allows the purge time to be updated to the purge flow through the
vent. This method is not dependent on a constant flow from the protective gas source. It
bases the purge time on the measured flow and not a set flow. This is very useful when the
protective gas supply pressure varies throughout the purging cycle or when it may vary from
one installation to another.
The following parameters must be entered for the dynamic purge time:
• Enclosure volume
• Number of exchanges
The purge time will be based on the measurement of the vent and evaluation of this
measurement from the EPCU. This allows recalculation of the time based on this
measurement. During the dynamic purge time, the user-interface will display the purge time
in a percentage starting with 0% and ending with 100% (purge time complete).
Purging Modes
Purging start-up can be set up in 4 different modes, which are explained below:
• STD – Standard mode requires the operator to engage the manifold solenoid valve
manually when purging and manually disengage when a successful purging is complete.
• SA – Semiautomatic mode requires the operator to engage the manifold solenoid valve
manually when purging. The EPCU will automatically disengage when a successful purging is
complete.
• FA – Fully-automatic mode will automatically engage the manifold solenoid valve when
safe pressure is detected and will automatically disengage when a successful purging is
complete.
• PV –The proportional mode will continuously control the flow rate during and after
purging. This allows maximum efficiency of the protective gas supply. This is very useful for
areas where there is a limited amount of the protective gas supply available.
Inputs
There are (4) intrinsic safety inputs for activation of various outputs and actions by the
EPCU. These inputs accept only a dry contact for activation and are supplied by the EPCU’s
galvanically isolated barrier. The assignments of the inputs for various actions are achieved
through the user-interface controller. Only one function can operate an input. These inputs
can bypass the system for live maintenance on the enclosure.