Daqu — Manual
4.7
Fuel Pressure
4.7
Fuel Pressure
Fuel pressure section does not tell much more than the oil pressure section.
All considerations are almost identical. The only difference is the operating
pressure range.
Two typical ranges are found for fuel pressure sensors:
0 - 1 bar (15 PSI)
for engines with carburetor. Typical operating pres-
sure is 0.3–0.35 bar.
0 - 5 bar (72 PSI)
for engines with fuel injection. Typical operating
pressure is around 3 bar.
For engines with fuel injection system a 10 bar pressure sensor is often used
– same as for the oil pressure. This reduces number of different sensors used
on an engine.
Most fuel pressure sensors use 1/8 – 27 NPT thread and some special sealant
to prevent fuel leaks.
4.8
Voltage
Daqu can measure voltages from 0 to +30 V DC on the channel C. The system
voltage is usually measured on this channel.
4.8.1
Installation
This connection does not power Daqu. Daqu gets power via CAN bus cable.
Daqu will work properly even when system voltage is not connected to the C
channel.
Since system bus may provide significant power, it is very important to install
an inline protection fuse on the wire that connects positive terminal of the C
channel with the system bus. The fuse shall be close to the system bus. The
fuse protects from shortcuts due to accidental slip of the wire. The measuring
current is negligible, so a low current fuse can be used. Figure 21 illustrates
an example.
4.8.2
Configuration
The table 11 shows correct channel settings.
35
©
Kanardia
2019
