A.O. Smith BFC Cyclone, Installation, User And Service Manual

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7.7 Electrical connections
Warning
Leave the water heater electrically isolated until you are ready to commission it.
Caution
The water heater is phase-sensitive. It is absolutely essential to connect the mains live
(L) to the live of the water heater and the mains neutral (N) to the neutral of the water
heater.
Caution
There must be no potential difference between neutral (N) and earth (
A
). Use an isolating
transformer (see section 7.7.3.1) in the supply circuit when there is a potential difference.
The figure shows a view of the terminal block, and the table explains the relevant
connections.
Fig. Terminal block
A. Screws
B. Cover
C. Terminal block
7.7.1 Preparation
In preparation, you must first remove the two covers, and the cover of the electrical
section.
Undo the screws of the covers.
Carefully remove the covers from the water heater.
The electrical section is now visible.
Loosen the 2 screws (A) and remove the cover (B) from the electrical section.
The connector block (C) is now visible.
Note
Consult the table for the connections and consult the electrical diagram for the electrical
component connections.
Mains voltage Isolating transformer Alarm Out Program
controlled External BUS
Primary Secondary pump ON/OFF link
N L
A
N L
1
A
N L
2
A
X
1
X
2
A
N L
3
A
X
3
X
4
X
5
X
6
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 to 20 21 22 23 24
w
c
1.
2.
3.
n
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