Lake Shore Model 331 Temperature Controller User’s Manual
Table 5-1. Curve Header Parameters
Name:
The curve name cannot be changed from the front panel. Curve names can only
be entered over the computer interface (up to 15 characters). The default curve
name is User xx, where xx is the curve number.
Serial
Num:
Identify specific sensors with serial numbers of up to 10 characters. The serial
number field accepts both numbers and letters, but the instrument front panel
enters only numbers. To enter both numbers and letters, enter curves over
computer interface. The default is blank.
Curve
Format:
The instrument must know the data format of the curve breakpoints. Different
sensor types use different data formats. The sensor inputs require one of the
formats below. The range and resolution specified are not always available at the
same time. Practical range and resolution depend on the sensor type.
Sensor Units
Sensor Units
Format
Description
Full Scale Range
Maximum Resolution
V/K
Volts vs. Kelvin
10 (V)
0.00001 (V)
Ω
/K
Resistance vs. Kelvin
10 K (
Ω
) 0.001
(
Ω
)
log
Ω
/K
log Resistance vs. Kelvin
4 (log
Ω
) 0.00001
(log
Ω
)
mV/K
mV vs. Kelvin
±100 (mV)
0.0001 (mV)
SP
Limit
A setpoint temperature limit can be included with every curve. When controlling in
temperature, the setpoint cannot exceed the limit entered with the curve for the
control sensor. The default is 375 K. Set to 9999 K if no limit is required.
Coeff:
The instrument derives the temperature coefficient from the first two breakpoints.
If it is set improperly, check the first two breakpoints. A positive coefficient
indicates the sensor signal increases with increasing temperature. A negative
coefficient indicates the sensor signal decreases with increasing temperature.
Table 5-2. Recommended Curve Parameters
Type
Typical Lake
Shore Model
Units Format
Limit
(K)
Coefficient
Recommended
Sensor Resolution
Silicon Diode
DT-470
Volts
V/K
475
Negative
0.00001 (V)
GaAlAs Diode
TG-120
Volts
V/K
325
Negative
0.00001 (V)
Platinum 100
PT-100
Ohms
Ω
/K
800 Positive
0.001
(
Ω
)
Platinum 1000
PT-100
Ohms
Ω
/K
800 Positive
0.01
(
Ω
)
Rhodium-Iron RF-100
Ohms
Ω
/K
325 Positive
0.001
(
Ω
)
Carbon-Glass CGR-1-1000
Ohms
log
Ω
/K
325 Negative
0.00001 (log
Ω
)
Cernox CX-1030
Ohms
log
Ω
/K
325 Negative
0.00001 (log
Ω
)
Germanium GR-200A-100
Ohms
log
Ω
/K
325 Negative
0.00001 (log
Ω
)
Rox RX-102A
Ohms
log
Ω
/K
40 Negative
0.00001 (log
Ω
)
Type K
9006-005
mV
mV/K
1500
Positive
0.0001 (mV)
Type E
9006-003
mV
mV/K
930
Positive
0.0001 (mV)
Type T
9006-007
mV
mV/K
673
Positive
0.0001 (mV)
Au-Fe 0.03%
No Longer Sold
mV mV/K 500 Positive
0.0001
(mV)
Au-Fe 0.07%
9006-001
mV
mV/K
610
Positive
0.0001 (mV)
Advanced Operation
5-3
