Lamtec ETAMATIC V, Быстрая справка

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5 Internal Burner Firing Rate Controller
NOTICE
If you change the setpoint, regard that also the on and off switchpoints are shifted, because
they were defined as difference value to the setpoint.
5.6 Thermostat and Control Range
The thermostat function switches the burner on and off on the basis of the temperature and/
or pressure value, but only when burner is released by the start signal. The control range is
formed by entering the controller setpoint value and the parameters P 802 (switch-on point),
P803 (upper control range) and P 804 (burner OFF). The cut-off hysteresis is divided into 2
ranges. The first part lies above the setpoint and forms the upper control range. The second
part lies below the setpoint and forms the lower control range.
The control range may lie asymmetrically around the setpoint.
The power control unit functions within the upper and lower control range according to its set
-
tings in the parameters and the default values.
If the actual value of the control unit reaches the shut-down range, the base firing rate request
is emitted. If the control unit’s setpoint exceed the shut-down range a control shut-off occurs.
This is done by internal processing. If the actual value drops below the lower control range, a
re-start can occur.
NOTICE
This function can replace the control thermostat, which is required on the plant.
It does not replace a safety thermostat.
5.7 Manual Control
It is also possible to switch the ETAMATIC V to "Manual Control" with the terminals. By short-
circuiting the Pt100 signal (e.g. bridge terminal 19 and 20) the burner firing rate controller is
switched off. The fuel/air ratio controller then directly follows the input at the default firing rate
input. The display shows LE instead of HA.
NOTICE
Only use manual control while monitoring the system.
Use keys 4 and 5 to change the value.
Press key 11 ENTER to confirm the new value
Press keys 7 and 8 simultaneously to leave this mode without changes.
Press key MANUAL to move the regular firing rate input of the firing rate controller.
Press the keys 2 and 3 to variegate the burner firing rate.
Press key MANUAL again to cancel firing rate controller.