25
mode (EGT SCROLL MODE) the EGT-values of 4 cylinders, the oil temperature and
water temperature are scrolled in the display. The actual temperature is displayed in
the top field of the temperature fields, the bottom field shows the corresponding
cylinder, e.g. CL1 for cylinder 1, CL2 for cylinder 2, etc. The oil temperature is
indicated by OIL and the water temperature by H2O. Oil and water are only displayed,
if the corresponding ports are activated (see section 2.3.1).
Type K thermoelements and –ports are suitable for monitoring high temperatures, e.g.
CHT or EGT. For water and oil temperatures usually Pt100 senders are used, because
they have a better resolution and precision at lower temperatures. The
ALPHA
ALPHA
ALPHA
ALPHA
MFD
has 4 Type K ports and 2 Pt100 ports.
The
ALPHA
ALPHA
ALPHA
ALPHA
MFD
constantly monitors all senders for faults, e.g. cable breaks. If an
error is found, the audio alarm is sounded through the Intercom and the respective
display starts flashing. The display of temperatures is substituted by three dashes (---).
Because of the way temperature senders work, they can only show a signal which
corresponds to a difference in temperature of the source and a comparison point. To
show the real actual temperature, the difference value must be compensated by the
outside air temperature. The
ALPHA
ALPHA
ALPHA
ALPHA
MFD
does this all the time with an internal
temperature sender.
WARNING!
As mentioned in section 2.3.1, unused temperature ports can be
deactivated in Set-Mode 31 to 36 in order to de-clutter the display. If a
temperature is not displayed even though a sender has been connected
correctly, check if the port has
not mistakenly been deactivated
!
5.5 Water Temperature
The water temperature is usually measured by a Pt100 temperature sender. It is
displayed in the TOP temperature field of the
ALPHA
ALPHA
ALPHA
ALPHA
MFD
display and is designated
by the >Water/Oil Temp< icon. With some engines, e.g. Rotax 912, CHT and water
temperature are measured together, i.e. the water temperature is measured at two
cylinder heads. In this case it is recommended using two Type K senders at the two
CHT ports of the
ALPHA
ALPHA
ALPHA
ALPHA
MFD
.
5.6 Oil Temperature
The oil temperature is measured with a Pt100 sender. The sender is connected to the
Pt100 Oil Temp port on the
ALPHA
ALPHA
ALPHA
ALPHA
MFD
. It is displayed in the LOWER temperature
field of the
ALPHA
ALPHA
ALPHA
ALPHA
MFD
display and is also designated by the >Water/Oil Temp<
icon. For further details see the following section 5.7.
