GDS GasVac LG-1, Руководство по эксплуатации

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TIME WEIGHTED ALARMS
(NOTE: THIS APPLIES TO OPT5,6,7,8 RELAYS)
Two types of time weighted alarms can be set using menu 31. STEL is a short time exposure level
which is a weighted average of gas level for the last 15 minutes. It is associated with one of the
four groups (5,6,7,8) of sensors. Each group may have any number of sensors within it and
whichever is the highest reading in the group, this reading is used to formulate the value of STEL.
LTEL is a long time exposure level taken over 8 hours and calculated in the same way as STEL.
Both STEL and LTEL have individual alarm settings but both act upon the same relay.
These alarms are rising only. Each gas must clearly be of the same type. If STEL or LTEL alarm
level is set to a value greater than zero, then this voting group becomes a TWA (Time Weighted
Average) group and the normal voting function is suppressed.
DEFAULTING THE PANEL
Individual sections of the panel can be defaulted rather than restoring all the defaults within
the panel. This is useful when one particular section of retained data needs to be reset. See
ENGINEER’S menu 32 for details.
DEFAULT THE WHOLE PANEL FROM POWER UP
At manufacture of a new processor board and possibly in service if a new set up is to be
installed, it is necessary to clear all system parameters and load default settings.
This can be done by pressing and releasing the processor reset button on the PCB at the same
time that the
SELECT (3) button is pressed and held down. Release the SELECT (3) button when
the LCD displays the message “Initialising NVRAM”.
Clearly, this is only to be done if you are sure that a complete default is required. Always ensure
that a copy of the old set up is available in a text file which could be reloaded if needed.