Viessmann EM-EA1 Installation And Service Instructions For Contractors page 7

Power supply
(cont.)
Danger
The absence of system component earthing can
lead to serious injury from electric current if an
electrical fault occurs.
The appliance and pipework must be connected
to the equipotential bonding of the building.
E
L1
N
C
D
B
Fig. 10
Power supply for extension
A
Power supply for heat generator control unit
B
Power supply 1/N/PE, 230 V/50 Hz
C
Fuse (max. 16 A)
D
Mains isolator, 2-pole, on site
E
Junction box (on site)
F
F
D
40
A
Isolators for non-earthed conductors
■ The mains isolator (if installed) must simultaneously
isolate all non-earthed conductors from the mains
with a minimum contact separation of 3 mm.
■ If no mains isolator is installed, all non-earthed con-
ductors must be isolated from the power supply by
the upstream circuit breaker with a minimum contact
separation of 3 mm.
Connect the power supply in accordance with the dia-
gram.
If the power supply to the appliance is connected with
a flexible cable, ensure that the live conductors are
pulled taut before the earth conductor in the event of
strain relief failure. The length of the earth conductor
wire will depend on the design.
Danger
Incorrect core assignment can result in serious
injury and damage to the appliance.
Never interchange cores "L" and "N".
!
Please note
Incorrect phase sequence can cause damage to
the appliance.
Ensure phase equality with the power supply of
the heat generator control unit.
Colour coding to IEC 60757
BN Brown
BU Blue
GNYE Green/yellow
7