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Siemens Building Technologies
Basic Documentation LMU54... / LMU64...
CC1P7494en
HVAC Products
9 Connection diagrams
07.11.2002
The contact material used with external signal sources (LP, RT, DHW flow switch, etc.)
should be gold-plated silver (also refer to «Technical data»).
Both the detector electrode and the ignition probe must be protected against electric
shock hazard.
Since the cable to the flame detector electrode must be well insulated against ground, it
must be protected against condensation, together with the detector electrode.
Input X1 for the unit’s power supply must be connected to the power supply network as
follows:
X1-1 to L
and
X1-2 to N.
Connection of functional earth to X1-3 must be made in compliance with regulations !
If the boiler or burner manufacturer wants to conduct additional insulation or high-
voltage tests, they can only be made after prior approval by Siemens !
Testing by the customer
U
