GEA Grasso - Page 48

Grasso
Refri
g
eration Division
GRASSO SYSTEM CONTROL
Chap. 2 - 12 638660E_chapter2.doc 01.2004/1
2.7.1.2 Switching sequence in case of too low oil differential pressure alarm during running
Output — compressor motor on
’Oil dif press’ OK
’Oil dif run’ timer active
’Low oil differential pressure’ alarm
Figure 2.14, Oil system monitor in case of too low oil
differential pressure alarm during running
•
If
(1) Output — compressor motor on equals 1
and
•
If
(2) ’Oil dif press’ OK equals 0
→
Then
(3) Start ’Oil dif run’ timer
•
If
(3) ’Oil dif run’ timer expired
and
•
If
(2) ’Oil dif press’ OK equals 0
→
Then
(4) ’Low oil differential pressure’ alarm