External Blocking Via Switching Contact - Viessmann Vitoladens 300-W Installation And Service Instructions For Contractors

Installation sequence
Electrical connections
Ensure DC separation between the earth conductor
and the negative pole of the on-site power source.
[{{] aBJ f-]
0-10V
+ - S P Ö L
U
+
Fig. 8

External blocking via switching contact

Connection options:
■ Plug
lH
■ EA1 extension (accessory, see separate installation
instructions)
When the contact is closed, the burner is switched off.
The heating circuit pump and (if installed) the circula-
tion pump for cylinder heating are switched according
to the set code (see the following table "Codes").
Plug
lH
A
1 L N
?
lH
Floating contact (when connected, remove jumper
A
between L and 1)
Codes
"4b:2" in group "General"/1
■
Effect of the function on the heating circuit pump:
■
coding address "d6" in group "Heating circuit" (only
for weather-compensated control units)
Effect of the function on the circulation pump for cylin-
■
der heating:
coding address "5E" in group "DHW"/3
16
(cont.)
fÖ
A
N N L
0 to 1 V No specification for set boiler water
temperature
1 V Set value 10 °C
10 V Set value 100 °C
!
Please note
Live contacts lead to short circuits or phase fail-
ure.
The external connection must be floating and
meet the requirements of protection class II.
EA1 extension
B
[{A [{S [{D
DE DE DE
A
Floating contact
A
EA1 extension
B
Codes
Set "3A" (DE1), "3b" (DE2) or "3C" (DE3) to 3 or 4 in
■
group "General"/1.
Effect of the function on the heating circuit pump:
■
coding address "d6" in group "Heating circuit" (only
for weather-compensated control units)
Effect of the function on the circulation pump for cylin-
■
der heating:
coding address "5E" in group "DHW"/3