685 Series
ComboPak
User’s Manua
l · Page 21
(except scripts and the function key definitions), and allow you to quickly recall
them. This is particularly useful when the instrument is used in multiple setups,
and the particular configuration of each setup can be stored and later recalled
for a quick reconfiguration.
To restore a unit to factory defaults, use the *RST (or *RST 0) command,
however, scripts and configurations are
not
erased, and user calibration data is
not
cleared. To reset the unit, including erasing scripts, configurations, and user
calibration data, you must use the *RST 1 command.
Thermal Considerations
The
ComboPak
is designed to provide high power in a small enclosure. Both
the laser and TEC sections of the
ComboPak
can be thermally overloaded if
operated at high currents with a low voltage, and each section handles the
thermal overload condition differently.
For the laser section, only the 2 Amp model of the
ComboPak
is at risk of a
thermal overload, and only when driving nearly a dead short at maximum
current. In this case, the driver will always respond by turning the output off and
generating an E-537 error message in an overload condition. Lower current
models (1 Amp and below) have no risk of thermal overload.
For the TEC section, the
ComboPak
will automatically protect itself by lowering
the TEC current until it is no longer in an overload condition. This may lower the
deliverable power to your TEC, but it will prevent any damage to the
ComboPak
. One exception to this is if you are operating in ITE (or constant
current) mode. In this mode, because you are specifying a specific drive current
for the TEC, if there is a thermal overload condition, the output will be turned off
and an E-438 error message will be generated.
If your output thermally trips, you can add a small series resistor (to the laser or
TEC, as appropriate) to remove some of the power from inside the unit.
Typically, a 1
0W 1Ω load resistor in series with the
output is sufficient, but higher
resistances and or power handling may be needed, depending on the voltage
and current configuration of your
ComboPak
. Please feel free to contact the
factory for more information and support.
Below is a graph that illustrates the minimum voltage requirements for the TEC
section of all
ComboPak
controllers:
