Newport LDT-5500B Series User manual

User’s Guide
Temperature Controller
LDT-5500B Series
70019907 November 2017

November 2017 1 70019907 LDT-5500B Manual
Table of Contents
Safety and Warranty Information ................................................................. 5
Chapter 1 : Introduction and Specifications ................................................. 9
Product Overview .......................................................................................................9
Features of the LDT-5500B Series include:...................................................................9
Available Options and Accessories ................................................................................ 10
Specifications ...........................................................................................................11
Chapter 2 : Operation ................................................................................ 13
AC Power Considerations ........................................................................................13
Rack Mounting................................................................................................................ 13
Power Up Sequence.................................................................................................13
USB ..........................................................................................................................14
Introduction to the LDT-5500B Series Front Panel ...................................................14
Adjustments .................................................................................................................... 14
Display ............................................................................................................................ 14
Parameters ..................................................................................................................... 15
Parameter Setup............................................................................................................. 16
Thermistor Sensor Cal.................................................................................................... 16
IC Sensors ...................................................................................................................... 16
Output and Control Mode ............................................................................................... 17
Error Indicators ............................................................................................................... 17
Analog Output................................................................................................................. 17
Back Panel Controls and Connections .....................................................................18
Sensor Select Switch...................................................................................................... 18
TEC Connector ............................................................................................................... 19
USB Connector............................................................................................................... 19
TEC Grounding Considerations...................................................................................... 19
General Operating Procedures.................................................................................20
Warm-Up and Environmental Considerations ................................................................ 20
Temperature Mode Operation ........................................................................................ 20
Resistance Mode Operation ........................................................................................... 21

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Chapter 3 : Remote Operation................................................................... 23
USB Driver Installation .............................................................................................23
Command Syntax .....................................................................................................23
Letters............................................................................................................................. 23
White Space ................................................................................................................... 23
Command Termination ................................................................................................... 24
Boolean Parameter Values............................................................................................. 24
Command Timing and Completion ................................................................................. 24
Error Messages ........................................................................................................24
Chapter 4 : Command Reference .............................................................. 25
LDT-5500B Series Device-Dependent Commands ..................................................27
Chapter 5 : Maintenance and Troubleshooting.......................................... 35
Calibration Overview ................................................................................................35
Recommended Equipment ............................................................................................. 36
Environmental Conditions............................................................................................... 36
Warm Up......................................................................................................................... 36
Calibration Adjustments............................................................................................37
Thermistor Calibration .................................................................................................... 37
Remote Thermistor Calibration....................................................................................... 38
AD590 Sensor Calibration .............................................................................................. 39
Remote AD590 Sensor Calibration................................................................................. 40
LM335 Sensor Calibration .............................................................................................. 41
Remote LM335 Sensor Calibration................................................................................. 42
ITE Current Calibration ................................................................................................... 43
Remote ITE Current Calibration ..................................................................................... 44
Troubleshooting........................................................................................................45
Appendix A: Steinhart-Hart Equation ......................................................... 47
Appendix B: Sensing Current and Thermistor Selection............................ 49
Thermistor Range.....................................................................................................49
Temperature Resolution ................................................................................................. 50
Selecting the Sensing Current ........................................................................................ 51
Selecting and Using Thermistors.................................................................................... 51
Appendix C: AD590 and LM335 Sensor Calibration.................................. 53
AD590 Sensor ................................................................................................................ 54
LM335 Sensor ................................................................................................................ 55
One Point Calibration Method......................................................................................... 56
Two Point Calibration Method......................................................................................... 57

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List of Figures
Figure 2.1 LDT-5500B Series Front Panel ...........................................................14
Figure 2.2 LDT-5500B Series Back Panel............................................................18
Figure 2.3 Back Panel TEC Connector ................................................................19
Figure B.1 Thermistor Temperature Range ..........................................................50
Figure C.1 AD590 Nonlinearity .............................................................................54

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List of Tables
Table 1.1 Accessories List ..................................................................................10
Table 1.2 Specifications ......................................................................................11
Table 2.1 SENSOR SELECT Switch Positions ...................................................18
Table 4.1 Remote Command Summary Reference List......................................25
Table 5.1 Recommended Calibration Equipment List .........................................36
Table 5.2 Troubleshooting Reference List ..........................................................45
Table B.1 Thermistor Sensitivity..........................................................................49
Table B.2 10kΩThermistor Temperature Range ................................................50
Table B.3 10kΩThermistor Voltage vs. Resolution.............................................50

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Safety and Warranty Information
The Safety and Warranty Information section provides details about cautionary symbols used in the
manual, safety markings used on the instrument, and the information about the Warranty including
Customer Service contact information.
Safety Information and the Manual
Throughout this manual, the words Caution and Warning indicate potentially dangerous or hazardous
situations which, if not avoided, could result in death, serious or minor injury, or damage to the
product. Specifically:
Indicates a potentially hazardous situation which can result in minor or moderate injury or
damage to the product or equipment.
Indicates a potentially dangerous situation which can result in serious injury or death.
Indicates visible and/or invisible laser radiation. Avoid direct exposure to the beam.
General Safety Considerations
If any of the following conditions exist, or are even suspected, do not use the instrument until safe
operation can be verified by trained service personnel:
Visible damage
Severe transport stress
Prolong storage under adverse conditions
Failure to perform intended measurements or functions
If necessary, return the instrument to ILX Lightwave, or authorized local ILX Lightwave distributor, for
service or repair to ensure that safety features are maintained (see the contact information on page
6).
All instruments returned to ILX Lightwave are required to have a Return Material Authorization (RMA)
number assigned by an official representative of ILX Lightwave Corporation. See “Returning an
Instrument” on page 5 for more information.

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Safety Symbols
This section describes the safety symbols and classifications.
Technical specifications including electrical ratings and weight are included within the manual. See
the Table of Contents to locate the specifications and other product information. The following
classifications are standard across all ILX Lightwave products:
Indoor use only.
Ordinary protection: This product is NOT protected against the harmful ingress of moisture.
Class I Equipment (grounded type).
Mains supply voltage fluctuations are not to exceed ±10% of the nominal supply voltage.
Pollution Degree II
Installation (overvoltage) Category II for transient overvoltages
Maximum Relative Humidity: <80% RH, non-condensing
Operating temperature range of 0°C to 40°C
Storage and transportation temperature of -40°C to 70°C
Maximum altitude of 3000m (9843 ft).
This equipment is suitable for continuous operation.
Safety Marking Symbols
This section provides a description of the safety marking symbols that appear on the instrument.
These symbols provide information about potentially dangerous situations which can result in death,
injury, or damage to the instrument and other components.
Caution:
Refer to
manual
Earth
Ground
Terminal
Alternating
Current
Visible
and/or
invisible
laser
radiation
Caution:
Risk of
Electric
Shock
Protective
Conductor
Terminal
Caution:
Hot Surface
Frame or
Chassis
Terminal
On: In position of push
control. The (I) denotes that
the mains are on.
Of: Out position of push
control. The (O) denotes that
the mains are on.

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Warranty
ILX Lightwave warrants this instrument to be free from defects in material and workmanship for a
period of one year from the date of shipment. During the warranty period, ILX Lightwave will repair or
replace the unit, at our option, without charge.
Limitations
This warranty does not apply to fuses, lamps, defects cause by abuse, modifications, or use of the
product for which it was not intended.
This warranty is in lieu of all other warranties, expressed or implied, including any implied warranty of
merchantability or fitness for any particular purpose. ILX Lightwave shall not be liable for an
incidental, special, or consequential damages.
If a problem occurs, please contact ILX Lightwave with the instrument’s serial number, and
thoroughly describe the nature of the problem.
Returning an Instrument
If an instrument is to be shipped to ILX Lightwave for repair or service, be sure to:
1. Obtain a Return Material Authorization number (RMA) from ILX Lightwave Customer Service.
2. Attach a tag to the instrument identifying the owner and indicating the required service or
repair. Include the instrument serial number from the rear panel of the instrument.
3. Attach the anti-static protective caps that were shipped with the instrument and place the
instrument in a protective anti-static bag.
4. Place the instrument in the original packing container with at least 3 inches (7.5cm) of
compressible packaging material. Shipping damage is not covered by this warranty.
5. Secure the packing box with fiber reinforced strapping tape or metal bands.
6. Send the instrument, transportation pre-paid, to ILX Lightwave. Clearly write the Return
Material Authorization number on the outside of the box and on the shipping paperwork. ILX
Lightwave recommends the shipment be insured.
If the original shipping container is not available, place the instrument in a container with at least 3
inches (7.5cm) of compressible packaging material on all sides.
Repairs are made and the instrument returned transportation pre-paid. Repairs are warranted for
the remainder of the original warranty or for 90 days, whichever is greater.
Claims for Shipping Damage
Upon receiving the instrument, inspect it immediately for any damage or shortages on the
packing list. If the instrument is damaged, file a claim with the carrier. The factory will supply a
quotation for estimated costs of repair. The customer is responsible for negotiation and
settlement with the carrier for the amount of damage.

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Comments, Suggestions, and Problems
To ensure getting the most out of ILX Lightwave products, direct any product operation, service
related questions, or comments to ILX Lightwave Customer Support. Contact ILX Lightwave in
whatever way is most convenient:
Phone [phone] or [phone]
Fax [phone]
Email [e-mail]
Mailing Address:
ILX Lightwave
31950 Frontage Road
Bozeman, Montana, USA 59715
When contacting ILX Lightwave, please have the following information:
Model Number
Serial Number
End-User Name
Company
Phone Number
Email Address
Description of the problem
If ILX Lightwave determines that a return to the factory is necessary, a Return Material Authorization
(RMA) will be issued. Please mark this number on the outside of the shipping box.
The customer or carrier is responsible for any shipping damage when returning an instrument to ILX
Lightwave. ILX Lightwave recommends insuring the shipment. If the original shipping container is not
available, place the instrument in a container with at least 3 inches (7.5cm) of compressible
packaging material on all sides.

November 2017 9 70019907 LDT-5500B Manual
Chapter 1 :
Introduction and Specifications
This chapter contains operation and maintenance information for the LDT-5500B Series
Temperature Controller:
Product Overview
Specifications
Product Overview
The LDT-5500B Series Temperature Controller is a microprocessor-based, precision
thermoelectric temperature controller designed for temperature control of laser diodes, detectors
and other temperature sensitive devices. The LDT- 5500B Series can be used for laser diode
testing, laser diode frequency stabilization, IR detector cooling, and the determination of
characteristics of electronic devices. The LDT-5500B Series combines high analog stability with
the versatility of a microprocessor-based instrument. The internal microprocessor controls the
operation of the LDT-5500B Series and performs the non-linear conversion of thermistor
resistance to temperature based on user-defined constants.
The LDT-5500B Series can be configured to operate with a wide variety of thermistor
temperature sensors and TE modules, as well as AD590 series and LM335 series temperature
sensors.
Features of the LDT-5500B Series include:
Intuitive front panel layout.
Large and easy-to-read green LED display.
Display resolution of 0.1 degree Celsius.
Output current limit control to safely operate TE module based devices.
Configurable for a variety of thermal sensors.
LDT-5525B is capable of 4A, 24W; LDT-5545B is capable of 5A, 50W.
Easy to use remote USB operation.
Closed-case calibration.

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Available Options and Accessories
Options and accessories available for the LDT-5500B Series Temperature Controller include the
following:
Table 1.1 Accessories List
DESCRIPTION MODEL NUMBER
Single Rack Mount Kit, LDX-3500 Series & LDT-5500 Series RM-134
Dual Rack Mount Kit, LDX-3500 Series & LDT-5500 Series RM-135
Laser Didoe Mount, 3-pin TO-Can, Temperature Controlled LDM-4405
Laser Didoe Mount, 3 & 4-pin TO-Can, Temperature Controlled LDM-4990
Telecommunications Laser Diodes Mounts
(For TO-Can, DIL, and Butterfly packages)
LDM-498X
TEC Controller to Unterminated Cable, 5A, DB15 Male to Bare Wire CC-501S
TEC Controller to Mount Cable, DB15 Male to DB9 Female CC-505S
Calibrated 10kΩThermistor TS-510
Uncalibrated 10kΩThermistor TS-520
RTD Temperature Sensor Converter TSC-599
Unipolar Control Adapter UCA-350
Not a complete list, visit website or contact sales staff for full list.
Please contact ILX Lightwave or visit www.newport.com/ilxlightwave for information on additional
options for applications.

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Specifications
Table 1.2 Specifications
LDT-5525B LDT-5545B
TEMPERATURE CONTROL
OUTPUT
Temperature Control Range1-99oC to 199.9oC
Temperature Setpoint Resolution 0.1oC
Temperature Setpoint Accuracy2
Thermistor ±0.2oC
AD590 ±0.2oC
LM335 ±0.2oC
Short Term Stability (1 hour)3<±0.006oC
Long Term Stability (24 hours)3<±0.01oC
Temperature Coefficient
TEC OUTPUT
Type Bipolar current source
Control Algorithm Smart Integrator, Hybrid PI
Compliance Voltage >6V DC (@ 4A) >10V DC (@ 5A)
Maximum Output Current 4.0A 5.0A
Maximum Output Power 24W450W5
Current Noise and Ripple6<1 mA rms
CURRENT LIMIT
Current Limit Range 0 to 4.04A 0 to 5.05A
Current Limit Set Accuracy ±50 mA
TEMPERATURE SENSOR
Thermistor 2-wire NTC
IC Sensors AD590/LM335
RTD Sensor72-wire RTD 100, 500, or 1 k
Thermistor Sensing Current 10/100 A
IC Sensor Bias AD590 = 8V
LM335 = 0.6 mA
Usable Thermistor Range 250 to 450,000 
User Calibration
Thermistor Steinhart-Hart, 3 constants
IC Sensor Slope and offset, two point
Analog Output 0 to 5V
Transfer Function8
10 A thermistor 10k/V
100 A thermistor 10k/V
AD590 100A/V
LM335 1V/V
TEC MEASUREMENT (DISPLAY)
Display Type 4 digit green LED
Temperature Range -99 oC to 199.9 oC

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Temperature Resolution
10 A thermistor 0.1oC
100 A thermistor 0.1oC
AD590 0.1oC
LM335 0.1oC
Accuracy3±0.5oC typical
Thermistor Resistance Range
10 A thermistor 2.5 to 450k
100 A thermistor 0.25 to 45.0k
Thermistor Resistance Resolution
10 A thermistor 0.1 k
100 A thermistor 0.01 k
Thermistor Resistance Accuracy
10 A thermistor ±0.05% of FS
100 A thermistor ±0.05% of FS
TE Current Range -4.00 to 4.00A -5.00 to 5.00A
TE Current Resolution 0.01A
TE Current Accuracy ±0.03A
CONNECTIONS
TEC I/O 15 pin D-sub Rear Panel
Analog Output BNC Front Panel
Communications USB Rear Panel
GENERAL
Power, VAC (50-60 Hz) VAC ±10%
Current Draw 100-120VAC 0.86A
230VAC 0.42A
100-120VAC 1.16A
230VAC 0.55A
Size 88mm x 185mm x 304mm
3.5” x 7.3” x 12”
Weight 3.6 kg (8 pounds)
Ambient Temperature Range Operating: 0 to 40 oC
Storage: -40 to 70 oC
Humidity <80% relative, non-condensing
Warm-Up 1 hour to rated accuracy
1. Actual temperature control range depends primarily on the thermal load, sensor, and TE moduleused.
2. Accuracy figures are quoted for a typical 10kthermistor and 100 A current setting. Accuracy figures are relative to
the calibration standard. Both resolution and accuracy are dependent upon the user-defined configuration of the
instrument.
3. Stability is a strong function of the thermal environment of the temperature sensor and the TE module. Ambient air
currents in particular can cause fluctuations of 0.1oC in an exposed mounting configuration.
4. Output power rated into a 1.5load.
5. Output power rated into a 2.0load. @100VAC, Reduced to 40W.
6. Measured with the instrument in ITE mode at half scale output over a bandwidth of 10 Hz to 10 MHz.
7. With use of optional TSC -599 Temperature SensorConverter.
8. 0 to 5V representing measured temperature.

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Chapter 2 :
Operation
This chapter describes how to install, adjust, and operate the LDT-5500B Series Temperature
Controller. It is divided into sections covering installation, familiarization and adjustment, and
normal operating procedures. This chapter also includes:
 Front Panel Features
 Front Panel Operations
 Installation Procedures
AC Power Considerations
The LDT-5500B Series Controllers can be configured to operate at nominal line voltages of 100,
120, and 230 VAC (±10%). This can only be done at the factory and need not be changed
before operating the instrument. Before operating the instrument, verify that the voltage
indicated on the back panel of the instrument matches the power-line voltage used in the
operating environment.
To avoid electrical shock hazard, connect the instrument to properly earth-
grounded, 3- prong receptacles only. Failure to observe this precaution can result
in severe injury or death.
Rack Mounting
The LDT-5500B Series Temperature Controller may be rack mounted by installing a rack mount
flange on either side of the enclosure. All rack mount accessory kits contain detailed mounting
instructions. Refer to Chapter 1 for applicable rack mount accessory part numbers.
Power Up Sequence
With the LDT-5500B Series Temperature Controller connected to an AC power source, pressing the
POWER switch will supply power to the instrument and start the power up sequence.
During the power-up sequence, the following takes place.
For two seconds, all indicators light up, and all of the 7-segment displays indicate “8”. All lights are
then turned off for two seconds. Next, two versions of firmware are displayed on the front panel: first
version number displayed is mainboard; the second is the front panel. After this, the sensor positions
are displayed for two seconds. After the power-up sequence, the unit is configured to the state it was
in when the power was last shut off (except for the display mode which defaults to the control mode).

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USB
The LDT-5500B may be controlled by PC using USB. The USB Type B connector is located on the
rear panel above the sensor select switch. See the Figure 2.2. The USB drivers (from either the ILX
Lightwave website or from the USB Flash Drive/CD) must be installed prior to making USB
connection. Please refer to Chapter 3 for more detailed instructions on operating the instrument
through USB.
Introduction to the LDT-5500B Series Front Panel
The LDT-5500B Series Temperature Controller's front panel contains displays and controls for the
Temperature Controller hardware. Each of the labeled areas on the front panel is described in this
chapter.
Refer to Figure 2.1 for the following discussions of the LDT-5500B Series Temperature Controller
front panel sections. The key words are in CAPITAL LETTERS for quick identification.
Figure 2.1 LDT-5500B Series Front Panel
Adjustments
The adjustment knob is used for entering values and can be disabled using the ENABLE (adjust
enable) button and indicator. In order to make any adjustment, the ENABLE indicator must be lit.
Pressing the ENABLE button toggles the ENABLE indicator on or off.
Display
The four digit display is used to show measurements, temperature and output set point, and
parameter values. Whenever a set point is being adjusted, the corresponding enunciator will blink.
After the set point value is reached, the enunciator will continue to blink for three seconds. After
which, the set point will be recorded.
The display SELECT button is used to select the measured current (ITE), sensor resistance, or
temperature. The set point type is determined by the MODE selection. Repeatedly pressing the

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display SELECT switch will cycle the display from ITE to temperature to resistance (with thermistor
sensors only) to set point.
When in ITE mode, the set point will be TE current in Amps.
When in R mode, the set point will be thermistor resistance in k. R mode is not available if the back
panel SENSOR SELECT switch is set to LM335 or AD590. R mode operation may offer improved
set point resolution (over T mode), depending on the desired temperature set point.
Note: If the control method or sensor current is changed, the set point will be stored.
When in T mode the set point will be temperature in °C.
Parameters
The LDT-5500B Series Temperature Controller allows adjustment of the following parameters, LIM I
(TE current limit), LIM T (temperature limit), GAIN (sensor feedback amplifier gain) and CONST
(sensor calibration values).
The LDT-5500B Series will limit the ITE output to the LIM I value, regardless of the set point or
control mode.
The temperature is limited (via the sensor feedback) to the LIM T value. If the sensor reads a
temperature which is greater than LIM T, the output will be disabled.
The GAIN value is used to control the sensor feedback gain, and thus the temperature settling time
and overshoot. GAIN values can be adjusted in discrete steps from 1 to 300. If the GAIN is set low,
the actual temperature will take longer to reach the temperature set point. If the GAIN is set too high,
the actual temperature may oscillate around the set temperature.
The optimum GAIN setting depends on the thermal load, temperature set point, and the type of TE
cooler. Set the GAIN to its lowest value and then try increasing it until the temperature oscillates
around the set temperature. Then, reduce the GAIN one step.

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Parameter Setup
The parameter SELECT button is used to view parameters. Repeatedly pressing the parameter
SELECT switch will cycle through the parameters.
When a parameter is selected for viewing, its value will remain on the display for three seconds. The
parameter value can be changed by pressing the SET button and turning the adjust knob. The
parameter LED will not blink when being adjusted. Three seconds after the parameter value has
been reached, the value will be stored and the display will revert to the last measurement mode.
Thermistor Sensor Cal
These are the constants of the Steinhart-Hart equation that the user enters to calibrate the TEC for
thermistor temperature conversions. The Steinhart-Hart equation is used to derive temperature from
the non-linear resistance of an NTC (Negative Temperature Coefficient) thermistor. For information
on setting C1, C2, and C3for thermistors, see Appendix A. For information on thermistor selection and
sensor current selection, see Appendix B.
The range of values for C1, C2, and C3are -9.99 to +9.99.
To read C1, C2or C3, press the parameter SELECT button until it sequences to CONST. While on the
CONST parameter, the SELECT button cycles through C1, C2, and finally C3. The display will indicate
which constant is currently selected, and can be adjusted or viewed by pressing the parameter SET
button, and turn the ADJUST knob until the correct value is displayed.
Appendix A contains an explanation of the Steinhart-Hart equation and a computer program to
determine these values for any thermistor.
IC Sensors
These are the constants entered to calibrate the TEC for AD590 and LM335 temperature
conversions.
When a linear sensor device (such as an AD590 or LM335) is used, a linear equation is used. If a
linear sensor's calibration is not known, set C1= 0.00, C2= 1.00. For more information on linear
sensor calibration, see Appendix C.
Appendix C contains information on sensor calibration constants for AD590 and LM335 sensors.
Since these devices are used over their linear range, the constants C1and C2are used in this case to
determine a linear approximation of the temperature, rather than the Steinhart-Hart non-linear
approximation which applies for thermistors. The appropriate algorithms are automatically
implemented whenever the sensor type is selected via the back panel SENSOR SELECT switch.
However, C1and C2must be changed by the user.

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Output and Control Mode
The MODE section contains the mode SELECT button, which is used to select the instrument control
mode. Repeatedly pressing the mode SELECT button cycles through the current (I TE), sensor
reference (R), or temperature (T) control modes. The LED indicators show the selected mode. The
MODE section also contains the OUTPUT button and indicator. The ON indicator is lit whenever the
output is on. Pressing the OUTPUT button enables the output of the instrument as indicated by the
LED indicator. With the output enabled, any thermal load connected to the instrument will be
controlled to the mode respective set point.
Conditions Which Will Automatically Disable the OUTPUT
1. Temperature Limit
2. Sensor Open (While Output On)
3. TEC Module Open (While Output On)
4. SENSOR SELECT Switch Moved (While OutputOn)
5. Operating Mode Changed (While Output On)
6. Short condition or low resistance (LDT-5545B only)
Error Indicators
The ERROR indicators become lit when the corresponding conditions occur. The SENSOR
OPEN light comes on whenever the sensor connections are open. The TE OPEN indicator
becomes lit whenever an open circuit (or a high impedance condition) occurs on the TE module
output when the output is on. When a TE OPEN condition occurs, the output will be shut off and
the indicator will remain on until the problem is resolved and the output is turned on again.
The T LIMIT light remains lit whenever the temperature limit is reached. The I LIMIT light will
remain lit whenever the I TE current limit is reached.
If a shorting condition occurs or a load which has < 1of resistance is used, the output will be
disabled and both the I LIMIT LED and TE OPEN LED will remain lit. This error can only occur
on the LDT-5545B due to the minimum load resistance specification.
Analog Output
An analog output signal is available at the ANALOG OUTPUT connector (BNC) on the front
panel. This signal is a voltage between 0 - 5.0 volts which is proportional to the measurement.
For example, an analog output signal of 2.5 volts (+0.5 volts) would represent a measurement
of 50% of full scale.

November 2017 18 70019907 LDT-5500B Manual
Figure 2.2 LDT-5500B Series Back Panel
Back Panel Controls and Connections
Refer to Figure 2.2 for the following discussions of back panel controls and connectors. There
are no user serviceable parts in the instrument, including the external fuses in the AC power
entry module.
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 2.1 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.
Table 2.1 SENSOR SELECT Switch Positions
SWITCH POSITION CODE
100 A -01-
10 A -02-
LM335 -03-
A
D590 -04-
The 10A and 100A designations are for the thermistor current source level. 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 C1and C2are used for a two-point conversion. For
more information on setting the constants for use with these sensors, see Appendix C.