Viessmann Vitocal 300-G Installation And Service Instructions Manual page 98

Installation sequence
Power supply
(cont.)
Two-stage (type BW 301.A + BWS 301.A)
X3.7
A
X3.6
3
3
kWh
E
3/N
D
F
4
Shown excluding fuses and RCD.
A Heat pump control unit (connection
on cross connect PCB)
B Instantaneous heating water heater
(on site)
C Compressor, heat pump stage 1
(type BW 301.A)
D High tariff meter
98
B
5
≈
kWh
3/N
4
G
E Ripple control receiver (contact
F Backup fuse ripple control receiver
G TNC system feed
H Economy tariff meter
K Compressor, heat pump stage 2
C K
4
3
H
4
open: power-OFF enabled)
(type BWS 301.A)
4