Fronius Ohmpilot Bedienungsanleitung Seite 80

Functional Many heating systems consist of a boiler and a buffer, with the central heating supplying
Description the buffer and a control system charging 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 Datamanager. By controlling the Ohmpilot, the Datamanager adjusts any sur-
plus energy that is available to zero. In detail, this takes place by continuously adjusting
the heating element connected to the Ohmpilot.
For this application, two heating elements are installed, with preference being given to
activation of the first heating element (9). Only once the maximum temperature 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 element 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 maximum tem-
perature 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 layering 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
therefore the amount of energy is rather small. In the lower part of the boiler, a high tem-
perature difference of, for example, 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 please refer to application example 6. If no temperature
80
1
INPUT - grid supply 3x 230 V
Spring balancer 1.5 - 2.5 mm
NOTE! Phase and neutral con-
ductors must not be mixed up.
Residual current-operated circuit
breaker is triggered.
2
OUTPUT - L2 heating element
3
OUTPUT - L3 heating element
4
Multifunctional relay output
5
OUTPUT up to 3 kW variable, max.
13 A resistive load
Spring balancer 1.5 - 2.5 mm
6
Hot water boiler
7
PT1000 temperature sensor
8
External source (e.g. gas-fired
heating)
2
9
Heating element 1 (max. 3 kW)
10
Buffer
11
Heating element 2 (max. 9 kW)
12
Residual-current circuit breaker
13
Circuit breaker max. B16A
2
14
Ferrite (included in delivery)