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Functionality of the cycles in HR3
1. VM1 (red-box valve):
* Controls inlet gHe to the Kaeser Compressor
* Closes if there is no pressure rise of '1 psi' (can be changed on the HR3 PLC Screen) in the buffer tank between the sample time period (there are two parameters: sample time period (mins), sample spacing (mins))
* Has a switch to change its mode to "MANUAL" mode which
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 > 50 psig, then it stays open to the outside tank regardless of the SV7 state until Buffer tank pressure < 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).
Recursive cycles in fault mode:
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