Sensor Select Switch - ILX Lightwave LDT-5525 User Manual

2.5.1 SENSOR SELECT Switch

The SENSOR SELECT switch is used to select sensor type and, in the case of thermistor sensor, the source current
level. Table 2.4 shows the SENSOR SELECT positions and corresponding position code. When the sensor switch is
changed during TEC mode operation, the new sensor position code will be indicated on the TEC display for three
seconds.
The 10 µA and 100 µA designations are for the current source level; thermistor sensor type is implied. When using a
thermistor, the supply current depends on the thermistor operating temperature range and the required temperature
resolution. Guidelines for setting this switch are contained in Appendix B.
The AD590 sensor operates as a current source which is proportional to the sensed temperature. The LM335 sensor
operates as a voltage source which is proportional to the sensed temperature. Both of these sensors are
approximately linear over their operating ranges. When they are used, the constants C1 and C2 are used for a two-
point conversion. For more information on setting the constants for use with these sensors, see Section 2.4.5 and
Appendix C.
SENSOR SELECT POSITION CODES
SWITCH POSITION
100 µA
10 µA
LM335
AD590
Table 2.1 SENSOR SELECT Switch Positions
2-9
CODE
-01-
-02-
-03-
-04-