SRS Labs CTC100, Руководство пользователя

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Operation 24
CTC100 Programmable Temperature Controller
Input filters
The CTC100 has several numeric filters for processing sensor readings. Except for the sensor
calibration, the filters are disabled by default and can be enabled by the user. In the order in which
they are applied, the filters are:
1. Sensor calibration (converts sensor reading in ohms, volts, etc. to temperature)
2. Follow filter (virtual channels only; makes the value equal to another channel)
3. Offset/gain (multiplies a channel by a gain and adds an offset)
4. Difference (subtracts the value of another channel)
5. Lowpass (filters out noise)
6. Derivative (takes the derivative of the signal with respect to time)
The filters can interact with each other. For example:
If the settings of filters 1 4 are changed and the lowpass filter is enabled, the effect of the
new setting on the sensor reading is lowpass filtered.
Changing the gain may have unpredictable results if the difference filter is enabled, and
changing the offset has no effect if the derivative filter is enabled.
Custom calibration tables have no effect if the follow filter is enabled.
C ustom calibration tables
If none of the built-in sensor calibration curves are appropriate for your sensors, a custom
calibration table can be used to convert the raw sensor reading in ohms, volts, etc. to a
temperature. Each channel can have its own custom calibration table.
Custom calibration tables can be loaded with a remote command or with a USB memory stick.
Format of custom calibratio n tables
a 100 platinum RTD that at 0°C has a resistance of 100 ohms:
units = °C
0, 100.00
10, 103.90
20, 107.79
30, 111.67
40, 115.54
50, 119.40
60, 123.24
70, 127.08
80, 130.90
90, 134.71
100, 138.51
Units: units that this table
converts readings to. If omitted, assumed to be Kelvins. The units can be any string of 4 or
fewer characters but must not contain any spaces, periods, plus or minus signs, or numbers. To
type the degree si
number pad.