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Building Technologies Division
Basic Documentation LME7...
CC1P7105en
Infrastructure & Cities Sector
1 Safety notes
29.11.2011
1.4 Electrical
connection of flame detectors
It is important to achieve practically disturbance- and loss-free signal transmission:
Never run the detector cable together with other cables
– Line capacitance reduces the magnitude of the flame signal
– Use a separate cable
Observe the permissible detector cable lengths (see Technical Data)
The mains-powered ionization probe is not protected against electric shock hazard.
Protection against accidental contact must be ensured
Locate the ignition electrode and the ionization probe such that the ignition spark
cannot arc over to the ionization probe (risk of electrical overloads) and that it
cannot adversely affect the supervision of ionization
Insulation
resistance
– Must be a minimum of 50 M
between ionization probe and ground
– Soiled detector holders reduce the insulation resistance, thus supporting
creepage currents
Earth the burner in compliance with the relevant regulations; earthing the boiler
alone does not suffice