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9 Appendix
WARNING!
If the ETAMATIC is used with an integral flame monitor, terminal 53 may not be connected to
any other components
The optical flame sensors are supplied together with a connecting cable of ca. 2 m length. The
line between the sensor and the flame monitoring unit may be extended up to a distance of
500 m. For implementing an on-site extension we recommend a separate screened, five-wire
extension cable that can be connected to the sensor cable via an FG 24 (with ex-applications)
or FG 21 connector box, e.g.
WARNING!
If the option "integral flame monitoring" is deactivated subsequently in the ETAMATIC (e.g. an
external flame monitoring should be used), up to base version 4.0 the automatic flame guard
plug-in card has to be removed from the ETAMATIC, from base version 5.0 on the bridge 450
(beside the 96-pole plug) has to be switched.
The cable's screening may not be used as a low-frequency carrying operational link. The sen-
sors should be so mounted at the inspection aperture, that the burner's flame is properly vis-
ible across the entire combustion facility's "operating range”. For selective monitoring, the
inspection aperture should be so placed that the sensor covers the monitored flame's root
(near the burner's mouth). Attention should be paid to the fact that with extended tube collars
the part of the flame, which is covered by the sensor, becomes restricted. If necessary, the
inspection aperture should be sealed with a suitable protective glass sheet.
9.3 Avoiding EMC Effects
The proper installation normally prevents from the EMC-adverse effects. In exceptional cases
it may be necessary by not traceable and /or not removable sources of interference to find an
adequate grounding point for the shielding.
1 In exceptional cases it is possible, that through the protected earth an interference level is
injected into the shielding. Unmotivated fault shut-downs (especially with low wanted sig-
nal) or temporary extraneous light may occur. In this cases the following may help beside
the fault clearance of the protected earth.
– a disconnection of the flame sensor shielding from the protective earth terminal at the
ETAMATIC and the connection with the GND of the flame sensor (terminals 22 or 44)
– In rarely cases the shielding may be disconnected like described in section a) and the
sensor housing may be grounded at the burner plate.
2 Adverse effects through coupling into the laid cable may be eliminated normally only with
the correct laying and in some cases with an adequate grounding point.
3 Adverse effects straight to the flame sensor may be suppressed with the reduction of the
sensitivity when there is a sufficient flame signal.
cable type: LiYCY (blue, red, green, yellow, white) 5 x 1 x 0.5 mm
2
(AWG 20)
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