The oil management control logic must include 2 steps.
Step 1 Oil boost function description
CC-000103
Normal
operation
Low oil level
>5 sec
Low oil level
Oil level not
recovered
Less than every
20min (TD2*)
Max 45
sec (TD1*)
Oil
Boost
Step 1
Step 2
Protection
Step 1 (oil boost)
if oil level sensor detects low
level for more than 5 seconds, oil is trapped in
the system. Oil boost is activated (VS speed is
increased). It increases refrigerant velocity in the
system and recovers oil. TD1 is the maximum
time to complete step 1. If oil is not recovered
within TD1 switch to step 2. If oil is recovered
within TD1, the compressor will come back to
normal operation.
TD2
is the minimum interval between two step
1. In case of low oil level detection within a time
<TD2, switch to step 1.
Step 2 (Protection)
If the oil is still lower than
the limit after having completed step 1, or if the
oil level drips again
within a time <TD2, the controller must move
forward in protection mode and stop the system
in alarm.
Return oil trapped in the system to compressor
by increasing refrigerant mass-flow in the system.
Enter condition:
Low oil level in VS compressor
detected by oil level sensor.
Cancel condition:
High oil level in VS compressor
detected by oil level sensor.
OR
t1>TD1, Oil boost duration exceeds Maximum Oil
boost duration
Control sequence:
1. At initial state, VS (variable speed
compressor) is ON.
2. Low oil level detected in compressor. Reset
and Start t1.
3. VS compressor speed must increase to
Fboost
4. When High oil level detected in VS
compressor speed must be decreased to the
initial speed
•
Reset and start t2
•
Reset
3
2
1
VS Cp
FB
OL
t2
t1
TD1*
CC-000104
VS Cp
Variable speed compress
FB
FBoost
OL
Oil lack
TD1*
TD1 Max.
Control logic
38
AB444226142054en-000101
Содержание VLZ065
Страница 2: ......
Страница 53: ...53 AB444226142054en 000101...