INFICON Composer Gas Concentration Controller - Manual (Page 115)

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Composer Operating Manual
4.3.5.3.1 Function and Numeric Keys
The data entry and process control portion occupies the upper right portion of
the front panel and consists of a numeric keypad and special function keys
described below.
STOP . . . . . . . . . . . . . . . . . . . . . . In Concentration Control mode pressing
this key halts all process control activities,
lights the STOP state indicator and sets all
flows to zero. This key is active in both the
operate and programming modes. This key
is not operative in Bulk Flow Control
configuration.
REF ZERO . . . . . . . . . . . . . . . . . . Pressing this key replaces the factory zero
with the current resonant frequency and
lights the display’s "User Zero" message.
The actuation of this key will be ignored
unless the display’s STEADY indicator,
Ú ,
is illuminated. The reference zero is used
as the basis of calibration and
concentration calculation. Pressing this
key when other than pure carrier gas is
present in the transducer will result in a
concentration offset and improper
concentration values, refer to
section 3.1.2
on page 3-1 .
This function is inoperative when a
non-zero MIN FLOW value is used, refer
to
section 4.3.5.2.7 on page 4-15 .
PROG . . . . . . . . . . . . . . . . . . . . . . Pressing this key switches the display
function between the operate modes and
the programming modes.
C , E . . . . . . . . . . . . . . . . . . . After satisfactorily entering the parameter’s
value, pressing the E key will place the
displayed value into memory and erase the
previous value, moving the cursor to the
next parameter. Pressing the C key will
erase the newly constructed value for that
parameter and display the previous value,
the cursor will remain at the current
parameter.