Configuration Manual
Version Document 
A
001 
A
ccess V4.X Configuration manual 
   11 (56)  2018-07-11 
Manual 
Frequency controlled fans can be controlled at a fixed rotational speed. The 
rotational speed is selected by setting a fixed output signal (0 – 100%). Values for 
normal and reduced speed can be configured for each fan. 
Fans that are run with a fixed output signal can also be compensated (see the 
section above). In this mode, pressure sensors are not needed. 
External 
Two 0…10 V input signals are used for direct control of frequency controlled fans. 
The signal is received from e.g. a VAV unit. The signal controls the fans 0…100% 
(0…10 V on the analogue output). Pressure transmitters are not used in this 
control mode. 
Supply air pressure and extract air slave 
The rotational speed of the supply air fan is controlled by a pressure transmitter 
(”Pressure supply air”) which is placed in the supply air duct. The extract air fan 
does not have a pressure transmitter, instead you let the output for the extract air 
fan follow the control signal for the supply air fan. A scaling factor can be added if 
the characteristics of the extract air fan are not the same as the characteristics of 
the supply air fan. (Only pressure control of the supply air fan is possible using this 
function.) The extract air fan will start directly at 50% after the start delay. Then the 
heating of the exchanger will work for this operating mode as well. When the 
supply air fan starts, the extract air fan will be slave controlled by the supply air 
flow. 
Supply air pressure and extract air flow slave 
The rotational speed of the supply air fan is controlled by a pressure transmitter 
(“Pressure supply air”) which is placed in the supply air duct. The extract air fan is 
controlled by the supply air flow, in order to achieve a balanced ventilation. A 
pressure transmitter ("Flow supply air") which is placed in the supply air fan cone 
gives a measured value of the present supply air flow. A corresponding pressure 
transmitter (”Flow extract air”) is placed in the extract air fan cone and gives a 
measured value of the extract air flow. 
The supply air flow is the setpoint used for control of the extract air fan. A scaling 
factor can be added if the extract air fan does not have the same characteristics as 
the supply air fan. 
Extract air pressure and supply air slave 
The rotational speed of the extract air fan is controlled by a pressure transmitter 
(“Pressure extract air”) which is placed in the extract air duct. The supply air fan 
has no pressure transmitter. Instead, the supply air fan output is made to follow 
the extract air fan control signal. A scaling factor can be added if the supply air fan 
characteristics are not the same as the characteristics of the extract air fan (only 
pressure control of the extract air fan is possible using this function). 
Extract air pressure and supply air flow slave 
The rotational speed of the extract air fan is controlled by a pressure transmitter 
(”Pressure extract air”) which is placed in the extract air duct. The supply air fan is 
controlled by the extract air duct flow in order to achieve a balanced ventilation. A 
pressure transmitter (“Flow extract air”) placed in the extract air fan cone provides 
a measurement of the current extract air flow. A corresponding pressure 










