Lake Shore Model 340 Temperature Controller User’s Manual
Instrument Programming
8-3
Setting resolution is also six digits in sensor units. The curve format parameter defines the range and
resolution in sensor units as shown in Table 8-1. The sensor type determines the practical setting resolution.
Table 8-1 lists recommended sensor units resolutions. For most sensors, additional resolution is ignored.
The breakpoints should be entered with the sensor units value increasing as point number increases. There
should not be any breakpoint locations left blank in the middle of a curve. The search routine in the Model 340
interprets a blank breakpoint as the end of the curve.
NOTE:
If the curve you wish to enter has similar parameters to an existing curve, first copy the similar curve
(as described in Paragraph 8.1.5) to a new location, then edit the curve to the desired parameters.
To enter a curve, press the
Curve Entry
key. Press
the
Next Setting
key until
Edit curve
is selected,
then press the
Enter
key. Use the
s
or
t
key to
select the desired curve number to edit, then press
the
Enter
key.
You may now enter the serial number (SN), Limit,
Format, and Sensor/Temp (K) breakpoint pairs. Use the
Previous Setting
and
Next Setting
keys to move
from one edit field to the next. Use the
I
and
D
keys to Insert or Delete lines from the breakpoint field. When
the edit is complete, press the
Save Screen
key. The
Saving user curves...
message appears for a few
seconds. If you do not wish to save the new curve, press the
Cancel Screen
key.
8.1.4 Front Panel Curve Copy
Curves can be copied from one location inside the Model 340 to another. This is a good way to make small
changes to an existing curve. Curve copy may also be necessary if the user needs the same curve with two
different temperature limits or needs to extend the range of a standard curve. The curve that is copied is
always preserved.
NOTE:
Copying an internal curve from one location to another is not the same as copying (or
downloading) a curve from a data card to the Model 340. The data card curve downloading
procedure is provided in Paragraph 8.4.
To copy a curve, press the
Curve Entry
key. Press
the
Next Setting
key until
Copy curve
is selected,
then press the
Enter
key.
Change to the desired curve number with the
s
or
t
key, then press the
Enter
key. The cursor jumps
to the To: selection. Again, use the
s
or
t
key to
select the user curve number (21 to 60) the curve will be copied to. (Empty user curves have zeros for data.)
NOTE:
The copy routine allows you to overwrite an existing user curve. Please ensure the curve number
you are writing to is correct before proceeding with curve copy.
Once the curve number to copy to has been selected, press the
Enter
key. The following message is
displayed:
Press SAVE SCREEN to copy, CANCEL SCREEN to abort
. If you press the
Save Screen
key,
the
Saving user curves...
message appears for a few seconds, then the display returns to the
CURVE
ENTRY
menu. If you press the
Cancel Screen
key, the curve is not copied and you are returned to the
CURVE ENTRY
menu.
8.1.5 Front Panel Curve Erase
When curves are no longer needed, they can be edited over or erased. Curves erase sets all identification
parameters to default and blanks all breakpoint values.
To erase a curve, press the
Curve Entry
key. Press the
Next Setting
key until
Erase curve
is selected, then
press the
Enter
key. Change to the desired curve number with the
s
or
t
key, then press the
Enter
key. The
following message is displayed:
Press SAVE SCREEN to erase, CANCEL SCREEN to abort
. If you press
the
Save Screen
key, the
Saving user curves...
message appears for a few seconds, then the display
returns to the
CURVE ENTRY
menu. If you press the
Cancel Screen
key, the curve is not erased and you
return to the
CURVE ENTRY
menu.
N a m e :
S N :
L im it:
F o r m a t:
C o e f f :
D T -4 7 0
D 2 0 4 9 6
4 9 9 .9 0 0
V / K
N e g .
(I)In s e r t
1:
2 :
3 :
4 :
5 :
S e n s o r
0 .0 9 0 6 2
0 .10 19 1
0 .113 5 6
0 .12 5 4 7
0 .13 7 5 9
(D )D e le te
T e m p (K )
4 7 5 .0 0 0
4 7 0 .0 0 0
4 6 5 .0 0 0
4 6 0 .0 0 0
4 5 5 .0 0 0
E d it C u r v e : # 2 3
N a m e :
S N :
L im it:
F o r m a t:
C o e f f :
D T -4 7 0
S ta n d a r d
4 9 9 .9 0 0
V / K
N e g .
1:
2 :
3 :
4 :
5 :
S e n s o r
0 .0 9 0 6 2
0 .10 19 1
0 .113 5 6
0 .12 5 4 7
0 .13 7 5 9
T e m p (K )
4 7 5 .0 0 0
4 7 0 .0 0 0
4 6 5 .0 0 0
4 6 0 .0 0 0
4 5 5 .0 0 0
C o p y C u r v e : # 1 T o : # 2 1