Viessmann Vitocal 300-G BW, Installation And Service Instructions Manual

Page: 173 / 216

173
w¢Z Mixer motor, heating circuit M2 -
CLOSE
w¢U Circulation pump, heating cir-
cuit M2
w¢I Cylinder primary pump (in case of
a primary system at the DHW cyl-
inder, shut-off valve)
w¢O Control of electric immersion
heater EHE for DHW cylinder
wYP Control of external heat source
wYQ Instantaneous heating water
heater control (stage 2)
wYW Control of AC-Box and relay for
separate cooling circuit pump
wYE Mixer motor, external heat source
- OPEN
wYR Mixer motor, external heat source
- CLOSE
wYT Circulation pump, direct heating
circuit A1 (if heating water buffer
cylinder is installed)
wYZ Circulation pump for cylinder heat-
ing (in case of a cylinder primary
system on the heat pump)
wYU DHW circulation pump
wYI Central fault message (zero volt
contact in the 230 V range)
wYO AC-Box
wXP NC-Box
Connection markings
■ Terminal strip X7:
Terminals 2X7.1 to 2X7.13
■ Terminal strip X8:
Terminals 2X8.1 to 2X8.13
For PCB overview, see from page 59.
Note
■ Total load of all electrical connections
max. 1000 W.
■ Terminals may already have been
allocated (subject to appliance ver-
sion). If this signal is required exter-
nally, completely remove the core or
insulate the core end; alternatively use
a twin wire ferrule.
■ The connections to neutral conductors
and earth conductors are not shown in
the following list. These are made at
PCB 1 (cross current circuit board) at
terminals strips 1X1.
?
(earth conduc-
tor) and 1X2.N (neutral conductor)
Function components 230 V on PCB 2 (motherboard, terminal strip X7)
Function
Explanation Connection
Control/demand of the
external heat source Zero volt N/O contact:
■ Closed = demand
■ Open = no demand
■ Breaking capacity 250 V~, 4(2) A
■ unsuitable for safety LV (
≤
42 V~)
2X7.1
2X7.2
N/A N/A 2X7.3
2X7.4
Connection and wiring diagrams
PCB 2: Function components 230 V
(cont.)
5368 522 UAE
Service