Section 6 Parameter Settings
72 FT722 & FT742 (RS485) – FF & PM Sensors – User Manual
6.4.15 HT.1: Set or Query General Heater Settings
$<listenerID>,HT<tsp>*<checksum><cr><lf>
$<listenerID>,HT?*<checksum><cr><lf>
$<talkerID>,HT=<tsp>,<%>,<temp>*<checksum><cr><lf>
$aa,HT=xx,xx,
xx*hh<cr><lf>
Heater control circuit set point temperature (degrees Celsius)
Disables the heater (factory default setting)
Read only parameter that returns the % of full scale heater current
limit
0% (heater off) to 99% (heater fully on)
Read only parameter that returns the current internal temperature of
the sensor, In ⁰C, in range 00 to ±99⁰C
Example 1
Set the sensor set point temperature to 5C. Verify that the command has been accepted.
Set heater set point temp
$WI,HT=05,00,+24*3B<cr><lf>
Example 2
Turn off the sensor heater. Verify that the command has been accepted.
$WI,HT=99,00,+24*3E<cr><lf>
Use the HT command to set the sensor heater parameters, including switching the heater on
or off and configuring the heater set point. It is possible to query the sensor’s internal
temperature. It is also possible to query the duty cycle of the heater, which specifies the
percentage of the current being drawn by the heaters.
By default the sensor requires a minimum of 11VDC for heater operation. This setting can be
modified on request by the factory or via the command detailed in Section 6.4.17.