Lenovo Neptune DWC RM100 - Fig.18 - Fill Pressure & Level Flow Chart (When Running)

CDU Operating & Maintenance Guide Page 24
Neptune DWC RM100 in-rack Coolant Distribution Unit
a = fill pump ‘switch on’ threshold
pressure (default 0.8 Bar (12psi))
b = fill pump ‘switch off’ hysteresis
pressure (default 0.2 Bar (3psi))
c = hysteresis pressure for low
pressure alarm (default 0.2 Bar
(3psi), non-adjustable)
d = system over pressure threshold
(default 6 Bar (87psi))
‘Fill Pump Request’
& manual
fill pump start
Y
RM100 water pressure
management
Has fill pump
run > 1 min?
Fill pump stops
N
Y
A15 – Water
Make-Up Empty
Has fill pump
run > 5 secs?
Y
A30 – Check
Water Make-Up
Fill pressure
(PS1) < a-c
for
>1 min?
Fill pressure
(PS1) ≥ a+b ?
Y
N
N
Fill pressure
(PS1) < a
for
>10 secs?
A27 – Secondary
Over Pressure
Fill pump stops
RM100 stops
System
pressure (PS2)
> d ?
Y
A32 – Secondary
Over Pressure
RM100 continues
to run
or (depending on setup)
N
Y
N
N
Unit running, with make-up
fill bag connected
A31 – System
Low Pressure
Fig.18 – Fill Pressure & Level Flow Chart (when running)