STIEBEL ELTRON SOM 6 PLUS - Manual (Page 13)

13
∆T-regulation
DT O:
Switch-on temperature diff.
Adjustment range: 2.0 ... 40.0°Ra
[1.0 ... 20.0 K]
in steps of 1 °Ra [0.5 K]
Factory setting: 12.0°Ra
[6.0 K]
DT F:
Switch-off temperature diff.
Adjustment range: 1.0 ... 39.0°Ra
[0.5 ... 19.5 K]
in steps of 1 °Ra [0.5 K]
Factory setting: 8.0°Ra
[4.0 K]
The controller works as a standard differential controller. If the
switch-on difference is reached, the pump is activated. When
the temperature difference falls below the adjusted switch-off
temperature difference, the relay switches off.
Note:
The switch-on temperature difference must be
at least 1 °Ra [0.5 K] higher than the switch-off
tempe rature difference.
DT S:
Nominal temperature difference
Adjustment range: 3.0 ... 60.0 °Ra
[1.5 ... 30.0 K]
in steps of 1 °Ra [0.5 K]
Factory setting: 20.0 °Ra
[10.0 K]
RIS:
Rise
Adjustment range:
2 ... 40 °Ra
[1 ... 20 K]
in steps of 2 °Ra [1 K]
Factory setting: 4 °Ra [2 K]
Pump speed control
A relative minimum pump speed can be allocated to the
output R1 via the adjustment channel
nMN. nMN:
Pump speed control
Adjustment range: 30 ... 100
in steps of 5 %
Factory setting: 30
Note:
When a load which is not speed-controlled is used,
the value must be set to 100 % in order to deactivate
pump speed control.
Minimum pump speed
When the switch-on temperature difference is reached, the
pump is activated at full speed for 10 seconds. Then, the
speed is reduced to the minimum pump speed value (factory
setting = 30 %).
If the temperature difference reaches the adjusted nominal
temperature difference, the pump speed increases by one step
(10 %). If the difference increases by the adjustable rise value, the
pump speed increases by 10 % respectively until the maximum
pump speed of 100 % is reached. The response of the controller
can be adapted via the parameter “Rise”.
Note:
The nominal temperature difference must be
at least 1 °Ra [0.5 K] higher than the switch-on
tempe rature difference.
4.2 Adjustment channels
Note:
For pump speed control, the operation mode of
relay 1 must be set to Auto (adjustment channel
MAN)
Note:
When the drainback option
ODB is activated, the
temperature differences DT O, DT F and DT S are
set to a fixed adjustment:
DT O
= 20 °Ra [10 K]
DT F = 8 °Ra [4 K]
DT S = 30 °Ra [15 K]
Previous adjustments made in these channels will be
overridden and may have to be entered again if
ODB
is deactivated later on.