Commissioning
4.3 Commissioning and operation
FIDAMAT 6-G
Operating instructions, 07/2006, A5E00478463
4-9
Setting the sample, zero and test gas pressures
Gas
Input pressure
Zero gas
500 – 1000 hPa rel.
Test gas
500 – 1000 hPa rel.
Sample gas (span)
500 – 1000 hPa rel.
1.
Connect the above-named gases to the rear of the device at the marked gas
connections. Their pressures must be able to be set outside the FIDAMAT 6-G and
should be around 1000 hPa.
2.
Now select function 62 "Set ext.pressure". With this function, you can switch the solenoid
valves built into the FIDAMAT 6-G for the gases on and off individually.
3.
Check the pressure for combustion air. Before the zero, test or sample gas is switched
on, this must be 480 hPa ±0/-5 hPa. If this is not the case, set the pressure with the
pressure regulator for combustion air on the rear of the device.
4.
Now, if you open the zero gas valve (function 62), for example, zero gas flows in the
FIDAMAT 6-G and the pressure for the combustion air increases.
5.
Now set the pressure externally for the zero gas such that the pressure gauge shows 500
hPa as precisely as possible (can be read using function 62, “Air” line). If the pressure for
combustion air exceeds 485 hPa, the FIDAMAT 6-G automatically switches over to the
"measure" operating state.
6.
Proceed in the same way with the other two gases (sample and test gas). The important
point is that the display pressure is as close as possible to the same value when each
particular gas is switched on (500 hPa ±2 hPa). If the pressure falls below 485 hPa, the
unit switches to the "standby" operating state; for example, whenever no measurements
are being conducted and therefore no sample gas is present.
See also
Measured value display (Page 5-4)
Entering a submenu (Page 5-5)
Set external pressure (function 62) (Page 5-37)
4.3.5
Measuring range
Measuring ranges / measuring spans
The desired measuring spans (start-of-scale value and full-scale value of measuring range)
can be defined with function 41. The start-of-scale / full-scale values are allocated to the
analog current values 0/2/4 mA to 20 mA.
If you enter the same value for the start-of-scale and full-scale values of a measuring range,
this measuring range is considered to not exist. Allocate the smallest measuring span (MS)
the measuring range 1 and the respectively next large one the measuring range 2... 4. In
general, the following is true for the allocation: MS1 < MS2 < MS3 < MS4.