BCU 460, BCU 465 · Edition 11.19
122
Project planning information
14 .3 Electrical connection
The BCU is designed for connection to a 1-phase sys-
tem. All inputs and outputs have a one-phase mains
supply. Other connected burner control units must use
the same phase of the mains supply.
The national standards and safety requirements must
be satisfied. If the BCU is operated in ungrounded/IT
systems, an insulation monitoring device must be pro-
vided to isolate it from the mains in the event of a fault.
The cabling of the safety circuits (e.g. pressure switches,
gas valves) outside enclosed installation spaces must
be protected from mechanical damage and stress (e.g.
vibration or bending) as well as short-circuits, short-
circuits to ground and cross-circuits.
Signal and control line for screw terminals max.
2.5 mm
2
(AWG 12), for spring force terminals max.
1.5 mm
2
(AWG 16).
Do not route BCU cables in the same cable duct as
frequency converter cables or cables emitting strong
fields.
External electrical interference must be avoided.