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Energy Measurement Commands (Thermopile Sensors):
This section is relevant for thermopile sensors measuring single-shot energy pulses. Some of the commands are
relevant also for pyroelectric/PD-C sensors measuring pulsed laser pulses, as will be noted below in a separate
section.
Force Energy Command ($FE):
$FE[CR] -> *[CR] {Forces sensor into energy mode. Needed if sensor started up in power-only mode. Sensor can be
set to start up in energy mode as default if required, by sending $HC S after sending $FE. When in energy mode,
sensor can continue to measure power using $SP etc. To switch off energy mode, send $FP command}
Energy Flag Command ($EF):
$EF[CR] -> *1[CR] or *0[CR] {Returns status of energy measurements, whether there has been a new energy
measurement since last Send Energy ($SE) command was processed}
Notes:
When starting up energy measurements, it is good practice to send the $EF command to check there is no “residual”
energy measurement already present, and if the command returns “1” the old measurement should be cleared by
sending the $SE command before continuing. See sub-section “Notes on Measurement Energy in Support Software”
below.
Send Energy Command ($SE):
$SE[CR] -> *1.2345E1[CR] (Energy in Joules), or “*OVER[CR]” {Returns latest energy value measured in Joules, or
"OVER" if last energy measurement was overrange. Returns "?NOT MEASURING ENERGY[CR]" if sensor is not
measuring energy but only power}
Notes:
The Energy value is returned using same format defined for $SP. The exponent value depends on the chosen energy
scale
If the power level saturates the internal A-to-D while measuring energy, $SE returns "OVER"
The $SE command will repeatedly return the last energy measurement until a new energy pulse arrives, the $EF flag
can be used to determine if a new energy measurement has arrived since the last time $SE was used
The maximum rate at which energy can be measured depends on the specific sensor parameters
See section below for suggestions on usage of this command in software.
Energy Status ($ES):
Returns status of energy measurements at this moment. Return value is one of the following codes:
"NOT IN ENERGY" if not measuring energy (see $FE)
"START" if energy measurements are resetting (when first entering energy mode it takes a few seconds for the
software to prepare for the first measurement)
"WAIT" if waiting for the next trigger to arrive
"INT" if integrating the present energy pulse
"VALUE" if a valid value is available (only for one cycle)
"TIMEOUT" if integration failed (power level did not drop low enough to end integration, only for one cycle)
"FINISH" after value is available, before new triggers are allowed
Energy Ready ($ER):
Sends *1 if an energy value is ready, or 0 otherwise. Does not relate to whether the value was queried using $SE.
When first entering the energy mode, or after changing the energy scale, the device will not be ready to receive and
measure a new energy pulse, and the command will return “*0”. When the device is ready to receive a new energy
pulse, the command will return “*1”. If a pulse is received and the device is triggered, the command will return *0
while integrating the measurement, until it is ready to receive the next pulse.
Energy Threshold ($ET):
Queries or sets energy threshold. Allows the customer to adjust the internal trigger level used for detecting the start
of an energy pulse.
0 or no parameter: Query