ero electronic LDE - Operative Mode; Preliminary Comments; SMART Algorithm

15
GB
5. OPERATIVE MODE
The display and modification of the operative
parameters can be protected by a secret code.
For more information see section 4.2.
5.1 PRELIMINARY COMMENTS
It is assumed, at this point, that the instrument has
been correctly configured as indicated in
Section 4.
- Model LME displays the value measured on the
upper display: the lower display is normally
used to display the operating set point (below
this condition is defined as “Normal display”).
- Model LDE displays the value measured (below
this condition is defined as “Normal display”) or,
alternatively, the operating set point (in this
case the SP led lights up).
To change from the display of the set point to
that of the value measured, or vice versa, press
pushbutton s.
All the parameters can be displayed sequentially
by pressing the FUNC pushbutton.
- Model LME displays the abbreviated name of
the parameter selected on the lower display, on
the upper display the value set.
- Model LDE displays alternatively the name of
the parameter and its value: during the
modification it displays only the value.
5.2 SMART ALGORITHM
This function gives best process control.
To enable the SMART function, press the SMT
pushbutton for more than 1.5 s, when the
instrument is in normal display mode. The SMT
LED will be lit continuously or flash according to
the algorithm automatically selected.
When the SMART function is enabled, the control
parameters (
PBPB
PBPB
PB,
TITI
TITI
TI,
TDTD
TDTD
TD and
rCrC
rCrC
rC) can be displayed
but not modified.
When it is dasired to disable the SMART function,
press the SMT pushbutton again (for more than
1.5 s) to turn the "SMART" OFF. The instrument
maintains the actual control parameters setting
and allows parameter modification.
NOTES:
1) During operation of the SMART function, the
relative cooling gain (if controlled by SMART) is
limited within the following ranges:
Cooling medium Span
Air 0.85 to 1.00
OIL 0.80 to 0.90
H
2
O 0.30 to 0.60
2) The SMART function uses a derivative time equal
to 1/4 of the integral time.
3) The limits of the proportional band settable by
the SMART function are programmed by
parameters P16, P17 and P18 .
4) The lower limit of the integral time settable by
the SMART function is programmed by
parameter P20 .
5) When ON/OFF control is programmed (Pb=0),
the SMART function is disabled.
6) SMART enabling/disabling can be protected by
the safety lock (see parameter P15).
lxe-1-B00.p65 10/18/02, 3:47 PM15