J&E Hall JEHSD-0600-M-3, Техническое руководство

Страница: 23 / 40

Issue: 01.05.2017 Page 23
Control Logic
Parameters for neutral zone compressor control
1. Preset differentials for neutral zone, activation zone and deactivation zone.
Neutral zone
The operating principle is schematized in the above figure:
Inside the neutral zone the capacity request sent by the controller is constant (except when there is a
modulation device and modulation is enabled inside the neutral zone) and the value satisfies the
pressure control request in those specific operating conditions. Therefore within this zone no device is
stopped or started.
In the decrease zone, the request also decreases at a rate that depends on the deviation from the set
point, and vice-versa in the increase zone the request increases proportionally to the deviation.
For the increase and decrease zones, the following can be used:
• Fixed times: the request decreases or increases constantly as time elapses.
• Variable times: the request decreases or increases more quickly (according to the settings) as the
deviation from the set point increases.
Note: The figure shows the increase and decrease with fixed times.