3
Installation
page 22
ELC X-Series-V1.3-09.16-GB
subject to technical alterations
3.3 Comments on the safety functions of the ELC
In addition to the safety functions included in all previous ELC-types such as earth fault
detection, temperature limit, safe operation in both short-circuit and open circuit at the lamp
output, the ELC X-Series includes an additional function in the form of the definite lamp
shutdown. To date this function was assured by external components, e.g. a power contactor
cutting off the mains supply voltage of the ELC.
The definite lamp shutdown is implemented using two independent circuits which can be
regarded as redundant functions in terms of the safety assessment of the installation. The first
lamp shutdown function contains a safety relay which cuts the voltage-output of the ELC via
hardware. This safety function can be monitored by appropriate processing of the feedback
contacts „Safety NC1 + Safety NC2“.
A second safety shutdown may be realized with the input „Init Signal IN“. Here the cut off of
the output voltage is based on software.
The status of both safety circuits may be read out by PROFIBUS. However they can not be
deactivated via software. It is therefore necessary to apply 24V to both inputs „Safety Relay
IN“ and „Init Signal IN“. If the safety fuctions are not used it is possible to set wire jumpers
between „24V_Out“ (X806.5) and „Safety Relay IN“ (X806.2) and „Init Signal IN“ (X806.3).
Fig. 13 on page 21 shows an overview of the circuits.
3.3.1 Safety relay
To set the ELC ready for operation, the safety relay K1 has to be activated by ap24V
to pin X806.2.
As long as the safety relay is not activated, lamp operation is not possible! There are two
feedback paths:
•
a normally closed relay contact. It may be tapped on pins X805.2 and X805.3.
•
the [Warning Register] of the PROFIBUS-input-data (see below and paragraph 5.3: Bit
4 {Safety Relay Open})
If the safety relay is deactivated during lamp operation, lamp operation will be shut down. After
reactivating the safety relay, the lamp has to be restarted.