14
24 VAC
This PCB module is galvanically separated
from the 24 VAC mains supply and is both
suitable for industrial installations with joint
24 VAC supply and individual installations,
which are supplied by a separate 230/24 V
safety transformer in the main electrical panel.
The module includes a double-chamber safety
transformer, which fulfils double-isolation
requirements when the cover is mounted on
the electronics box. Power consumption is less
than 1 VA/1 W.
Diagram 6
National regulations for electric installations must be observed. The 24 VAC module
can be connected/disconnected by the district heating station’s personnel, where-
as the fixed 230/24 V installation in the main electrical panel must only be carried
out by an authorized electrician.
Note:
This module cannot be supplied by 24 VDC (direct current).
230/24 V, safety transformer
The 24 VAC module is specially suited for installation together with
a 230/24 V safety transformer, e.g. type 66-99-403, which can be
installed in the main electrical panel before the safety relay. When
the transformer is used the total power consumption of the meter
incl. the 230/24 V transformer will not exceed 1.7 W.
Figure 10
2.2.3 Mains supply cable
ULTRAFLOW® 54 is available with mains cable H05 VV-F for either 24 V or 230 V
(l=1.5 m):
Figure 11
Mains cable (2x0.75 mm²), max. 6 A fuse
”H05 VV-F” is the designation of a strong PVC mantle, which withstands max. 70°C.
Therefore, the mains cable must be installed with sufficient distance to hot pipes
etc.
