Viessmann EM-EA1 Extension Installation And Service Instructions Manual page 12

Connections
Connecting the Fault Message Input and Fault Message Output
Legend
A Fault message facility
B Junction box
12
EM-EA1 Extension Installation / Service
Connecting the fault message input and fault message
output (continued)
Connection without system blocking via 120V fault
message input: fD
Fault message input 43-1 and conductor L of the
power supply at plug fÖ must be connected in phase.
Rated current at floating fault message output hH:
Max. 1A ~.
The fault message is active if 120V voltage is present
at digital input 43-1. Floating fault message output hH
is switched over from "Ö" to "S".
Connection with system blocking via 24V fault message
input: DI1
Example: Connecting a condensate removal pump
Note:
External contacts at DI1 must be potential-free.
Rated current at fault message output hH:
Max. 1 A ~.
The fault messaging is active if the digital fault
message input DI1 is closed. The boiler is blocked.
Floating fault message output hH is switched over
from "Ö" to "S". Fault message F.104 is shown.
Connecting only message facility: hH
Example: Buzzer with illuminated signal switched in
parallel
(continued)