Project Planning Information; Cable Selection; Ionization Cable; Ignition Cable - Honeywell BCU 460 Technical Information

Project planning information

6 Project planning information

6 .1 Cable selection

Use mains cable suitable for the type of operation and
complying with local regulations.
Signal and control line: max. 2.5 mm
Cable for burner ground/PE wire: 4 mm
Burner ground connector may also be located outdoors.
Do not route BCU cables in the same cable duct as
frequency converter cables or cables emitting strong
fields.

6 .1 .1 Ionization cable

Use unscreened high-voltage cable, see page 81
(Accessories).
Recommended cable length: max. 50 m.
Lay cable individually and, if possible, not in a metal
conduit.
Install well away from mains cables and interference
from electro-magnetic sources.
Do not lay together with ignition cable.

6 .1 .2 Ignition cable

Use unscreened high-voltage cable, see page 81
(Accessories).
Cable length for integrated ignition. max. 5 m (16.4 ft).
Avoid external electrical interference. The longer the ig-
nition cable, the lower the ignition capacity.
BCU 460, BCU 465 · Edition 03.16l
2 .
2 .
Lay cable individually and, if possible, not in a metal
conduit.
Do not lay UV/ionization cable and ignition cable to-
gether and lay them as far apart as possible.
Screw the ignition cable securely into the ignition trans-
former and feed it out of the unit on the shortest pos-
sible route (no loops) – use the left-hand M20 plastic
cable gland.
Only use radio interference suppressed electrode plugs
(with 1 kΩ resistor) for ignition electrodes, see page
81 (Accessories).

6 .1 .3 UV cable

Recommended cable length: max. 50 m.
Install well away from mains cables and interference
from electro-magnetic sources.
Do not lay together with ignition cable.

6 .2 Ignition electrode

6 .2 .1 Electrode distance

Gap between electrode and burner ground:
2 mm ± 0.5 mm.

6 .2 .2 Star electrodes

We recommend using 7.5 kV ignition transformers on
burners with star electrodes.
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