Connecting The Operating Mode Changeover: Di1 To Di3; Connecting External Heating Circuit Hook-Up - Viessmann EM-EA1 Installation And Service Instructions Manual

Installation sequence
Connecting external functions
Note
No galvanic separation is required between the earth
conductor and the negative pole of the on-site power
source.
The 0 to 10 V hook-up generates the following default
output for the heat generator:
≙
< 1 V 0 %
≙
1 V 10 % or lower modulation limit
≙
10 V 100 %

Connecting the operating mode changeover: DI1 to DI3

jF jF [{] DI1 DI2 DI3 [{] [{]
1 2 3 4 1 2 3 4 5 6
Fig. 5
External contacts at DI1, DI2 and DI3 must be poten-
■
tial-free.
When making the connection, adhere to the require-
■
ments of protection class II. That is 5.0 mm air and
creep paths and 2.0 mm insulation thickness against
'live' components.
Weather-compensated operation
Contact open: Normal operation

Connecting external heating circuit hook-up:

Only in conjunction with weather-compensated opera-
tion.
External heating circuit hook-up is only possible on the
extension kit with rotary switch setting 1; see
page 20.
No additional parameter settings on the heat generator
are required.
jF jF [{] DI1 DI2 DI3 [{] [{]
1 2 3 4 1 2 3 4 5 6
Fig. 6
12
(cont.)
If 230 V voltage is present at digital input 43-1, the
external default output is enabled.
Contact closed:
Demand for all installed heating circuits simultane-
■
ously, with the respective programmed set room tem-
perature of the individual heating circuit:
DI1 Reduced room temperature
DI2 Standard room temperature
DI3 Comfort temperature
Continuous operation or room temperature-
dependent operation
Contact open: Normal operation according to set time
program
Contact closed:
Set flow temperature demand for the system
■
Demand for all installed heating circuits simultane-
■
ously, at the respective programmed temperature
level of the individual heating circuit:
DI1 Reduced flow temperature
DI2 Standard flow temperature
DI3 Comfort flow temperature
(Only with continuous operation)
Configuration of at least 2 heating circuits with the fol-
lowing mode of operation:
■ Contact closed: External demand active. Heating cir-
cuit is supplied with heat.
Contact open: External demand not active. Heating
■
circuit is not supplied with heat. Independent of the
current set room temperature or time program. There
is no frost protection for the heating circuit.
The following status messages are displayed on the
heat generator control unit:
– Heating circuit 1: S.94
Heating circuit 2: S.95
–
Heating circuit 3: S.96
–
Assignment:
DI1 Heating circuit 1
DI2 Heating circuit 2
DI3 Heating circuit 3