Lake Shore 218S, Руководство пользователя

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Lake Shore Model 218 Temperature Monitor User’s Manual
Operation 4-7
4.5.1 Optimizing the Update Rate
The maximum update rate of the Model 218 is 16 readings per second allowing all eight inputs to be
read twice each second. Turning off unused inputs (Paragraph 4.1.5) permits a higher reading rate on
fewer sensors (refer to Table 4-2). For maximum efficiency, split sensors evenly between the two
input groups when using fewer than eight sensors. All new readings can be read from the instrument
with either the IEEE-488 or serial interface. The display update rate remains at twice per second.
Table 4-2. Sensor Configuration Update Rates
Group 1-4
Inputs On Group 5-8
Inputs On
Readings/Second
(Individual Input)
1 — 16
1 5 8
1, 2 5, 6 4
1-4 5-8 2
4.6 CURVE SELECT
Each sensor input of the Model 218 must be assigned a temperature response curve if it is used to read
temperature. If no temperature response curve is assigned to an input it will read in sensor units only.
During curve selection only curves appropriate for the sensor type will be displayed so sensor type
must be selected before curves.
Standard curves are included in the instrument and can be assigned to sensor inputs that match them.
Standard curves included in the Model 218 are listed in Table 4-3.
Users may store a unique 200-point user curve for each of the eight inputs if standard curves are
inadequate. CalCurves™ for Lake Shore calibrated sensors store as user curves. User curves can be
entered from the front panel or with a computer interface. The built-in SoftCal™ algorithm can also
generate improved curves for DT-470 diodes and platinum sensors stored as user curves. Refer to
Chapter 5 for details about user curves. User curves must be stored in the same location number as the
sensor input. Once an appropriate user curve stores for a sensor input, it can be selected just like
standard curves, but it can be used for only one input.
Table 4-3. Standard Curves Included in the Model 218
Curve
Number
Display
Name
Sensor Type
Lake Shore
Sensor #
Curve Name
Temperature
Range
1 DT-470 Silicon Diode DT-470 Curve 10 1.4 – 475 K
2 DT-500 Silicon Diode DT-500-DRC-D Curve D 1.4 – 365 K
3 CTI Silicon Diode N/A CTI Curve C 10 – 320 K
4 DT-670 Silicon Diode DT-670 DT-670 1.4 – 500 K
6 PT-100
100
Ω
Platinum RTD
PT-100 DIN 43760 30 – 800 K
7 PT-1000
1000 Ω Platinum RTD
PT-1000 DIN 43760 30 – 800 K