ETAS
Functional Description
ES430.1 - User’s Guide
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5.7
Sensor Heating
The heating of the sensor can be powered on independently of the power sup
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ply of the module as the heater control is supplied with power via the sensor
cable.
5.7.1
Operating Modes
Depending on the measuring tasks and where the lambda sensor is installed,
the sensor may have to be operated (heated) independently from the actual
measuring. The following settings are available for this purpose in the calibra
-
tion software:
• “External Signal”
The setting “External Signal” is selected if the lambda sensor of the
ES430.1 is installed in the exhaust system of a vehicle and the sensor
heating is to be operated independently of measuring by being con
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trolled with an external signal (e.g. terminal 15).
• “On”
This setting is selected when no cooling of the sensor is required for a
specific set of measurements as the delay between measurements
would otherwise be too long.
This setting can, for example, avoid the lambda sensor cooling off in
start-stop tests with the control of the heater control via terminal 15.
• “Off”
“Off” is selected when the sensor only has to be ready for use when the
measurement system (sensor, ES430.1 and calibration software) is
active. An example of an application for this setting is working on the
test bench.
5.7.2
Heater Control
The heater control of the ES430.1 is adapted to the lambda sensor LSU4.9. The
heater curve ensures a short warm-up phase and minimum thermal load of the
sensor. The curve controls the relative heating performance of the sensor until
the working temperature of 780° C has been reached.
The state of the heater control (enabled/disabled) depends on the following
components:
• the operational state of the ES430.1 (“On”, “Off”, “Standby”),
• a heater control parameter selected in the calibration software,
• an external voltage for heater control as well as
• the supply voltage range of the sensor.
TIP
The operating modes of the sensor heating described below only apply if the
module is off or on “Standby”. When the ES430.1 is in operating mode "On",
the lambda sensor is always heated!
