KROHNE CORIMASS G-MFM 4085 EN - Manual (Page 93)

93
8.9 Status Warnings
The MFC 085 can detect a number of anomalous conditions during operation. These are
classed into four groups as follows :
LIGHT
These include :
–
Mass flow >2x primary head rating.
– Temperature outside operating range
– Mass total overflow.
Typically these indicate a problem with the use of the instrument, not the instrument itself.
OUTPUT
These warnings occur where the converter is trying to drive a signal on either the current or
frequency output which is outside the selected range. For example: Max flow = 10kg/min but
actual flow is 15kg/min. If the current output was set for mass flow then it would saturate at
20mA (10kg/min) plus over-range. Saturation of the outputs in this way may or may not be a
problem for the operator, so it is optional as to whether a warning is set or not in this case. (If
required, the process alarm could be used to indicate independently the saturation of the
outputs). In addition, if the Process Alarm is used to detect that a measured value is out of
range then this also generates an output warning.
SEVERE
These include any fault that causes the primary head to stop vibrating. This may be due to large
quantities of air in the process fluid or to poor clamping of the instrument. Severe errors may
also be due to a hardware fault. The instrument will restart as soon as the fault clears.
FATAL
Fatal errors indicate a major fault with the converter. In this case the converter stops completely
and then tries to restart as if it had just been switched on. Normally such errors will require
repair by service personnel.
Viewing and acknowledging warning messages
Whenever a warning occurs the display will start to flash and the status arrow on the display will
be set. The flashing display enables the operator to see from a distance that a problem has
occurred. The operator can now inspect the list as follows:
Begin from measuring mode.
Key Display
line 1 line 2
↵
CodE 2 - -
↑
CodE * -
→
RESET MASS
↑
MSG. LIST
→ ≡
2 Err
≡
MASS FLOW
(Flow > 2 x Nominal tube flow)
The "
≡
" symbols indicate that
this warning has not previously
been acknowledged.
→
2 Err I1 SAT
(Current output saturated)
↵
QUIT (YES)
↵
MSG. LIST