Control Units - Viessmann ESS CHP Overview

Electronics

6.5 Control units

6.5.1 Cylinder level control unit SFR
Article number
Function
Standard delivery
Delivery
Note
Subject to changes due to technical improvements
CHP accessory range – 01/2010
CHP module type
for all CHP module types
Cylinder level control unit SFR to select or deselect a CHP module
Capture:
At the SFR control unit, the top and bottom PT100 sensors of the buffer cylinder are captured, assessed
and displayed.
Module selection:
To select the module, the switching point and time delay can be selected for the top and bottom cylinder
sensors.
If the temperatures in the cylinder fall below both switching points (cylinder empty), the CHP module is
selected.
If the upper switching point is exceeded, the module remains operational until the lower switching point
has also been exceeded (cylinder full). Only then is the CHP module deselected.
The module then remains deselected until the temperatures fall back below both cylinder sensor limits.
Pump selection:
With the upper cylinder sensor, the cylinder discharge is also controlled.
If a set temperature is exceeded, the cylinder discharge pump is selected.
If the temperature falls below the switching point of the upper cylinder sensor, the pump is stopped.
This prevents cold cylinder water being pumped into the heating flow.
Boiler block:
A possible option, if the upper cylinder sensor has exceeded a certain temperature (cylinder full), is to
then block the boiler via a zero volt contact so that the available heat is also drawn from the cylinder.
If the temperature falls below the set value again (cylinder empty), the boiler is re-enabled after an
adjustable delay.
All values and time delays are freely adjustable.
• Cylinder level control unit SFR in separate wall mounted casing
Control panel: 380 x 380 x 210 mm (H/W/D)
IP rating: IP41
Colour: RAL 7035
Max. ambient temperature: 45 °C
Max. relative humidity: 70 %
VDE: 0660/500
Cable entry: below
Door hinges: right
• Delivery of loose accessories:
2 PT100 sensors 220 mm with sensor well 1/2"
(power supply from module control field)
Control panel complete with all necessary fuses and relays, wired to terminals ready for connection.
The wiring required between control unit and PT100 sensors is installed on site.
On-site requirements:
• 1/2" female connection: cylinder top
• 1/2" female connection: cylinder bottom
As loose accessories for on-site installation
For further information and diagrams, please see the "Technical series natural gas CHP project
management".
ESS Viessmann
710-00-0060 7424555
ESS Energie Systeme & Service GmbH
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