Fronius Ohmpilot Bedienungsanleitung Seite 105

(9) Heating element 1 (max. 3 kW)
Buffer
(10)
(11) Heating element 2 (max. 9 kW)
(12) Residual-current circuit breaker
Automatic circuit breaker max. B16A
(13)
(14) Ferrite (included in scope of supply)
Many heating systems consist of a boiler and a buffer, whereby the central hea-
ting supplies the buffer, and a control system feeds the hot water boiler via a
pump. As with thermal photovoltaic systems, the Ohmpilot is also capable of
heating the hot water boiler first and then the buffer, so that the maximum
amount of photovoltaic surplus energy can be stored.
The Fronius Smart Meter records the current power at the feed-in point and
transfers the data to the inverter. By controlling the Ohmpilot, the inverter adjus-
ts any surplus energy that is available to zero. In detail, this takes place by conti-
nuously adjusting the heating element connected to the Ohmpilot.
For this application, two heating elements are installed, with preference being gi-
ven to activation of the first heating element (9). Only once the maximum tempe-
rature in the boiler (6) has been reached is the second heating element activated
in a continuously variable manner, so that the remaining energy can, for example,
be stored in a buffer.
If no temperature sensor is connected to the Ohmpilot, after 30 minutes the
Ohmpilot attempts to output energy via the first heating element once again. If a
temperature sensor is present, the device switches back to the first heating ele-
ment as soon as a temperature difference of 8°C is reached (compared to the
temperature measured prior to switch-over).
This switching can also be used for layering in a boiler/buffer, so that the maxi-
mum temperature is reached in the top part of the boiler using minimal energy
and the remaining energy is stored in the lower part of the boiler. By using laye-
ring in a storage tank, it is also possible to store significantly more energy, as a
minimum temperature is normally maintained in the top part of the boiler. This
means that the temperature difference and thus the amount of energy is rather
small. In the lower part of the boiler, a high temperature difference of, for ex-
ample, 50 °C can be used.
Both the first and the second heating element can be 1-phase or 3-phase. For
two 3-phase heating elements, see
sensor is fitted, an external source (e.g. gas boiler) must be used to ensure the
minimum temperature is met.
Alternatively, the Ohmpilot can also ensure the minimum temperature. This may
result in electricity being sourced from the grid. The maximum temperature must
be set on the heating element thermostat. If heating element 1 (9) does not have
a thermostat, the Ohmpilot can also carry out this task as an alternative (see
chapter Optional settings
have a thermostat.
NOTE!
Heating at the same time.
At no point can both heating elements be heated simultaneously.
Application example
on page 122). However, heating element 2 (11) must
6. If no temperature
105