Lake Shore Model 340 Temperature Controller User’s Manual
5-4
Measurement Operation
To select a temperature response curve, press the
Input Setup
key. The input setup setting screen will
appear with the input letter in the top left hand corner. Use the
s
or
t
key to select an input. Press the
Enter
key or the
Next Setting
key to display the input parameters for that input. Press the
Next Setting
key until
the curve field is highlighted and then use
s
or
t
key to select a curve from the list. Press the
Enter
key or
the
Next Setting
key and to advance to the next parameter. (If curve selection was not successful, press the
Next Setting
key and verify the appropriate type selection). Press the
Save Screen
key to store the changes
in the Model 340.
Table 5-3. Standard Curve Table
Curve Setting
No.
Sensor Type
Model Number
Curve Name
Temp. Range
Table
DT-470
1
Silicon Diode
DT-470
Curve 10
1.4 – 475 K
A-1
DT-500-D
2
Silicon Diode
*DT-500-DRC-D
Curve D
1.4 – 365 K
DT-500-E1
3
Silicon Diode
*DT-500/DRC-E1
Curve E1
1.4 – 330 K
A-2
PT-100
4
Platinum RTD 100
PT-100
DIN 43760
30 – 800 K
PT-1000
5
Platinum RTD 1000
*PT-1000
DIN 43760
30 – 800 K
A-3
Type K
6
Thermocouple
Type K
Type K
3.15 – 864 K (1500 K
†
)
A-4
Type E
7
Thermocouple
Type E
Type E
3.15 – 622 K (930 K
†
)
A-5
Type T
8
Thermocouple
Type T
Type T
3.15 – 670 K
A-6
AuFe .03%
9
Thermocouple
Chromel-AuFe 0.03%
Chromel-AuFe 0.03%
3.50 – 500 K
A-7
AuFe .07%
10
Thermocouple
Chromel-AuFe 0.07%
Chromel-AuFe 0.07%
3.15 – 610 K
A-8
DT-670 11 Silicon
Diode
DT-670
DT-670
1.4 – 500 K
A-9
* Curves supported but sensors no longer available through Lake Shore.
†
Temperature range extended when using ±50 mV Range.
5.3 FILTER AND MATH
Some simple arithmetic features have been included in the Model 340 as a convenience to the user. Filter,
Max, Min and linear equation can be applied to an input reading. As shown in Figure 5-1, the filter can be
applied to all readings for an input. The results of Max, Min, and linear equation can be shown on the display
in combination with the actual input reading. The display format screen is used to configure the display.
5.3.1 Filter
The Model 340 can apply an averaging filter to any sensor input. The filter is designed to prevent electronic
noise that is picked up on the sensor lead wires from showing on the display. It is enabled or disabled for all
of the reading formats of an input at the same time. A number of readings filtered and filter reset window can
be changed by the user to meet their application. The control equation has a filter that is enabled
independently from the input filter.
To turn on the filter for an input, press the
Math
Setup
key. The
MATH COMPUTATIONS
screen
appears with the
Input
field highlighted. Use the
s
or
t
key to select an input. Use the
Enter
or
Next Setting
key to move the cursor to
FILTER
Enable
. Use the
s
or
t
key to select
ON
. The
default setting is On.
The user may change filter behavior by changing the number filter readings. Although more filter readings
settle the display reading more, it is not always appropriate to select many filter readings. More filter readings
also slow display reading response to real temperature changes in the load.
To change on the filter readings (points) for an input, press the
Math Setup
key. You see the
MATH
COMPUTATIONS
screen. The
Input
field is highlighted. Use the
s
or
t
key to select an Input. Use the
Enter
or
Next Setting
key to move the cursor to
FILTER Points
. Use the
s
or
t
key to select the desired
number. The minimum number of points is 2, the maximum is 64. The default setting is 10.
Some users do not want the filter to slow the response of the display reading when large deliberate changes
in temperature are made. The filter window parameter allows the user to set the limit for a large temperature
change. If an unfiltered reading differs from the filtered reading by more than the filter window limit, the filter
will be restarted. The filter window limit is set in percent of full scale range for the selected input type.
To change the filter window for an input, press the
Math Setup
key. You will see the
MATH
COMPUTATIONS
screen. The
Input
field will be highlighted. Use the
s
or
t
key to select an Input. Use the
Enter
or
Next Setting
key to move the cursor to
FILTER Window
. Use the
s
or
t
key to select the desired
percentage. The minimum is 1%, the maximum is 10%. The default setting is 1%.
E n a b le :
S o u r c e :
E n a b le :
P o in ts :
W in d o w :
O N
T E M P K
O N
10
1%
<m o r e >
M A T H S E T U P
M A X / M IN
F IL T E R
In p u t: A