ILX Lightwave LDC-3700B Series User Manual Download Page 124

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C O M M A N D R E F E R E N C E

Command Reference

7/01

LDC-3700 Series

109

C H A P T E R

The TEC:TOLerance command allows the programmer to determine the TEC temperature
tolerance, and time window for it to occur, in order that the operation complete flag be set after a
"TEC:OUTput 1" command is issued or the set point is changed.

Parameters

One or two <nrf values>; the first represents the temperature tolerance, in

C, with a range of 0.1

to 10.0

C; and the second represents the time window, in seconds, with a range of 0.001 to 50.0

seconds.
This command may be used in conjunction with the TEC:COND? to test for and delay further
program activities until the TEC temperature reaches its set point to the specifications of the
TEC:TOLerance command.
For example, if the set point is 10

C, tolerance is 0.2

C for 5 seconds, and the TEC output is turned

on, the user may issue the TEC:COND? query and read back the response to ensure this set point
is reached before continuing. In this case, the TEC will not set bit 9 of the TEC condition register
until its TEC load temperature is within 0.2

C of 10

C for a period of 5 seconds.

Notes

The LDC−3700B Series Laser Diode Controller defaults to a tolerance of 0.2

C for 5 seconds,

unless changed by the TEC:TOLerance command.
In R mode the temperature and time parameters are both in effect, as in T mode.
In ITE mode, the temperature parameter is not used. A fixed value of 10 mA is used instead of the
temperature parameter, and only the time window may be adjusted.
If the tolerance is set too tight it may never be achieved. This is due to the calibration of the set point
and measurement values.

Examples

"Tol 0.5,10" −action: the LDC−3700B Series Laser Diode Controller’s TEC controller will be in
tolerance when the temperature is within 0.5

C for a period of 10.000 seconds.

"TOLer 0.1,1.05" −action: the LDC−3700B Series Laser Diode Controller’s TEC controller will be in
tolerance when the temperature is within 0.1

C for a period of 1.050 seconds.

"TEC:MODE:ITE; TOLer ,10" −action: the LDC−3700B Series Laser Diode Controller’s TEC
controller is set for ITE mode, and will be in tolerance when the ITE current is within 10 mA for a
period of 10.000 seconds.
"Tec:Mode:R; TOLer 0.1,2.5" −action: the LDC−3700B Series Laser Diode Controller’s TEC
controller will be in tolerance when the temperature is within 0.1

C for a period of 2.500 seconds.

The TEC:TOLerance? query allows the programmer to determine how the TEC temperature
tolerance is set.

Notes

The tolerance of the LDC−3700B Series Laser Diode Controller temperature controller may be used
to delay programming after an "TEC:OUTput 1" command is issued or the set point is changed.
The TEC tolerance specification is also used in the TEC status event and condition registers, and so
entering or exiting TEC temperature tolerance may be used to generate service requests.

Examples

"Tec:Tol?" −response: "0.2,5", means the LDC−3700B Series Laser Diode Controller has a TEC tol−
erance setting of 0.2

C with a time window of 5.000 seconds.

"TEC:TOL?" −response: "1.0,20", means the LDC−3700B Series Laser Diode Controller has a TEC
tolerance setting of 1.0

C with a time window of 20.000 seconds.

TEC:TOLerance

OMMON

EVICE

EPENDENT

RONT

ANEL

TEC:TOLerance