Danfoss EIM 365 User Manual page 16

Superheat controller, type EIM 365 (PV01)
Table 13: Te Control mode
Symbolic name
Kp Te
Tn Te
Te Reference
Protection or Limiter features
EIM 365 has protection features and Limiter features that prevents the system from operating under bad conditions
or gives indication towards it, these features are
• Superheat close
• MOP (Maximum operating pressure)
• LOC (Loss of Charge indication)
Superheat Close
EIM
Applicable
SH close is a protection feature, When the SH values go below the SH close value, the controller will close the valve
faster.
Symbolic name
n22 SH close
Maximum operating pressure (MOP)
EIM
Applicable
In order to reduce the current to the compressor it is possible to control the maximum operating pressure of the
evaporator. If the evaporator pressure exceeds the "MOP" limit, the valve opening degree is controlled by the MOP
function which will keep the pressure below the "MOP" limit. This function takes precedence over the superheat
control, so during MOP control the superheat is not controlled.
The MOP function can be disabled by setting the "MOP" to the maximum value (2000 equaling 200 bar absolute).
When the pressure reaches the set MOP point, an increase in OD is restricted. If the pressure reaches MOP + 0.5 Bar,
an increase in OD is prohibited, and instead the OD will start to decrease. If the pressure goes below the MOP point,
the controller will start to regulate the superheat normally.
The MOP controller consists of a separate PI control, which settings can be changed by setting "Kp MOP" and "Tn
MOP". A large Kp will lead to a large change in opening degree even at small changes in the evaporator pressure but
may lead to instability. A large Tn will lead to a slow reacting system, while a small Tn will lead to a fast-reacting
system
Figure 10: MOP controlling
bar
© Danfoss | Climate Solutions | 2022.09
PNU
3115
3116
3117
365
✓
PNU
3027
365
✓
Description
Kp proportional gain while in Te control mode
Tn integration time while in Te control mode
Te reference while in Te control mode
Description
Superheat close level. If the superheat goes below
this value, the valve will close faster.
BC415322248492en-000101 | 16