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2. SV7:
* There are two threshold values: closing-threshold and opening-threshold that can be set via the HR3 PLC Screen
* Operating closing-threshold is 70 psi
* Operating opening-threshold is 90 psi
* There is a check-valve of 50psig bypassing this SV7 (i.e. if the Buffer Tank pressure (PSW4) > 50 psig, then it stays open to the outside tank regardless of the SV7 state until Buffer tank pressure (PSW4) < 50sig)
* There is a setting called "SV7 stays closed when compressor idle" which couples to the Kaeser cycles (IDLE → LOAD → STANDSTILL ).
If it is "YES" (which seems to be the default): then SV7 is OPEN when the Kaeser Compressor is in the "LOAD" state (is shown as a dark arrow (left-to-right))
If it is "NO": then SV7 is OPEN when the Kaeser Compressor is in the "IDLE" state (is shown as a hollow arrow (left-to-right).
3. Kaeser Compressor (reference Kaeser 9_5869_33 USE SM Operating Manual.pdf):
* Has two control modes "DUAL" and "QUADRO" (see Section 4.4.2 page 26 on the Kaeser 9_5869_33 USE SM Operating Manual.pdf)
* DUAL: Switch between LOAD (when it reaches preset-minimum), and IDLE (when it reaches preset-maximum). When the preset Idling time has elapsed, the machine switches to READY/STANDSTILL mode.
* QUADRO: Switch between LOAD and READY/STANDSTILL after short periods of being IDLE.
Following extended times in various operating modes, the machine switches from LOAD to READY/STANDSTILL. The time in LOAD and IDLE operating modes are taken as minimum runtime.
Recursive cycles in fault mode:
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