Evco EVDRIVE03 - Page 25

EVCO S.p.A. EVDRIVE03 | User manual ver. 3.7 | Code 144EPDE374
Page 25 of 76
function (Ph31) setting to 2), the parameter sets for the PID control are determined by the digital input status: set 1 is
selected if the input is low, set 2 is selected if the input is high. If no DI is configured for parameter set modification,
the data is taken directly from SH parameters set selection (SetP).
With the operation mode selected, the regulator uses the related SH set-point parameter. This is a fundamental
parameter for the proper functioning of the control algorithm. A low set-point ensures a higher evaporator
performance, lower temperatures, and minimum variations, but has the disadvantage that liquid may reach the
compressor.
The algorithm uses different regulation parameters, depending on the working area:
- if the measured error is lower than Fast action threshold (Fath), a more aggressive algorithm is used (Fast
action (Fast))
- if the measured error is between Neutral zone high threshold (PNHi) and Smart band zone threshold (Pcz) a
smart algorithm is used.
- if the measured error is between 0 and Neutral zone high threshold (PNHi) no regulation is performed
All the input parameters, with the exception of the Main control type (Pcty), are acquired at every main cycle.
Pcz
PNHi
FaTh
0
Fast
Normal control
No regulation (dead
Smart
Normal control
Err