DURAG D-LX 200, Руководство пользователя

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Design and Function
The throughout dual-channel design (see Figure 4.3: Block diagram on
page 34) allows the elimination of regular interruption of the photoelectric
current (shuttering) and mechanical wearing parts.
4.1.4 Error shutdown
If an error is detected in the safety-relevant software and hardware
components during internal self-monitoring of the flame monitor, an error
shutdown and internal lockout must be triggered. The relays of the flame
signal and readiness for operation signal drop out and the Fault (Error) LED in
the front panel illuminates, while the Power LED starts to flash (for meaning of
LEDs see page 40).
Actuation of the internal reset key (behind the front panel of the D − LX 200,
D − LX 720) acknowledges an error shutdown and enables restarting of the
flame monitor. Actuation of an external reset key also acknowledges an error
shutdown and enables restarting, but the flame monitor must be in the error
position for this purpose. A reset can also be performed by temporarily
removing the power supply.
All LEDs go out when the reset key is pressed.
Irrespective of the device status (flame signal ON / OFF or fault), the relays
drop out after a mains break or actuation of the reset key, and the flame
monitor program restarts.
4.2 Device description
The housing of the Compact Flame Monitor D − LX 200, D − LX 720 comprises a
break-proof, coloured, temperature and chemical resistant plastic material
(polyamide PA 66). It contains the control unit and the integrated optical flame
sensor.
Figure 4.4: D − LX 200
The features of the Compact Flame Monitor include:

Consistent dual-channel microcontroller system (Chan. 1 and Chan. 2) for
control and monitoring of the safety-relevant flame monitor functions with
continuous self-monitoring,
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D − LX 200, D − LX 720