n
Connection status (STATUS)
When the boiler is locked out, the alarm signal may be transmitted via
a potential-free contact (maximum 230 V, 1A) on the
Nc
and
C
terminals on the connector.
n
Connection (OTm)
The interface communicates with the boiler regulator via the
OpenTherm
BUS. The
OTm
connection must be connected to the
OpenTherm
input
OT
of the boiler control.
n
Analogue input (0-10 V)
This control can be based on temperature or heat output. The two
controls are described briefly below. For analogue control, the 0-10
V signal must be connected to the interface.
n
Analogue temperature-based control (
*
)
The 0-10 V signal controls the boiler flow temperature between 0°C
and 100°C. This control modulates on the basis of flow temperature,
whereby the heat output varies between the minimum and maximum
values on the basis of the flow temperature set point calculated by
the controller.
A jumper (
2
) on the interface is used to select either temperature
control (
*
) or heat output control (
%
).
Jumper 2 Input signal (V) Temperature ºC Description
*
0 - 1,5
0 - 15
Boiler off
1,5 - 1,8
15 - 18
Hysteresis
1,8 - 10
18 - 100
Temperature required
n
Analogue heat output-based control (%)
The 0-10V signal controls the boiler output between 0% and 100%.
The minimum and maximum values are limited. The minimum output
is linked to the boiler’s modulation depth. where the heat output
modulates between the minimum and maximum value based on the
flow temperature set in the boiler.
Jumper 2 Input signal (V) Heat output (%) Description
%
0 - 2,0
(1)
0 - 20
Boiler off
2,0 - 2,2
(1)
20 - 22
Hysteresis
2,0 - 10
(1)
20 - 100
Heat output requested
(1) Dependent on the minimum modulation depth (set speeds, standard 20%)
T000785-A
1
2%
2
2
CALORA TOWER GAS 15S EX CALORA TOWER GAS 25S EX
CALORA TOWER GAS 35S EX
5. Installation
22/04/2016 - 300026141-001-07
45
