4.5 Commands
4 – 31
Laser Trip-o
ff
on Min Temperature
ATMN(?)
{
z
}
Set (query) the laser to trip o
ff
if the minimum temperature is ex-
ceeded
{
to
z
=
(
NO 0
,
YES 1
)
}
.
If set to
ATMN
YES
, the LDC500 requires the TEC temperature sensor
to remain above the
TMIN
setting. Note that the TEC controller
does not need to be active, but the temperature sensor must remain
connected and in-range, as well as reading above
TMIN
, if
ATMN
YES
is set.
Note that if the LDC500 is operating with the sensor model set to
“none” (resistance units), then arming
ATMN
will cause shut-down
if the sensor
TRAW?
value is less than
TRMN
, in k
Ω
. If the sensor
has a negative temperature coe
ffi
cient, this will correspond to the
greatest
temperature of the operating band,
not
the lowest.
Front panel:
LD :/@ABB
48
.
ATMN NO
Example:
4.5.9
TEC limit commands
TEC Current Limit
TILM(?)
{
f
}
Set (query) the TEC current limit
{
to
f
}
, in A.
The absolute value of the TEC current is limited to the value set
by
TILM
. When the TEC is in CT mode, the PID temperature loop
will saturate when the current limit is reached, and the TEC
ILim
indicator will light steadily. In TEC CC mode, the current setpoint is
limited to this value.
Note that lowering the
TILM
value below the (absolute) value of
TCUR
has the side e
ff
ect of “dragging” the
TCUR
setting with it,
towards zero.
Front panel:
"#
( *
.
TILM 3.0
Example:
LDC500 Series Laser Diode Controllers
