GGHFM 57.60 (MAF Meter System Pulsations) - Revision history

TTQS at 17:10, 14 January 2012

2012-01-14T17:10:00Z

TTQS at 17:01, 14 January 2012

2012-01-14T17:01:19Z

TTQS at 16:59, 14 January 2012

2012-01-14T16:59:35Z

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TTQS at 15:18, 11 October 2011

2011-10-11T15:18:33Z

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MattDanger at 22:09, 29 September 2011

2011-09-29T22:09:11Z

TTQS at 06:23, 14 September 2011

2011-09-14T06:23:28Z

TTQS at 17:32, 11 September 2011

2011-09-11T17:32:12Z

TTQS at 17:31, 11 September 2011

2011-09-11T17:31:17Z

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TTQS at 17:29, 11 September 2011

2011-09-11T17:29:38Z

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TTQS at 15:14, 9 September 2011

2011-09-09T15:14:56Z

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@@ Line 175: / Line 175: @@
 KFPUKLP12: pulsation-influencing adjustment elements 1 and 2
 Parameterization of the code words CWHFMPUKL1 and CWHFMPUKL2:
 Definition of adjustment element 1 for taking pulsation into account
 CWHFMKLPU1:

@@ Line 52: / Line 52: @@
 PUKANS = 1.0
 <u>Application Procedure</u>
@@ Line 62: / Line 63: @@
 . When using an alternative plug-in sensor, check the linearization curve is appropriate for the mounting position used.
 <u>Requirements for the Application of the Pulsation Map</u>
@@ Line 158: / Line 160: @@
 .8794
 |}
 <u>Application of the Pulse Maps KFPU, KFPUKLP1, KFPUKLP2, KFPUKLP12</u>
@@ Line 176: / Line 180: @@
 Definition of adjustment element 1 for taking pulsation into account
-−
 CWHFMKLPU1:
@@ Line 187: / Line 191: @@
 Definition of adjustment element 2 for taking pulsation into account
 CWHFMKLPU2:
@@ Line 224: / Line 227: @@
 <u>Abbreviations</u>
 {| border="1"

← Older revision		Revision as of 22:09, 29 September 2011
Line 791:		Line 791:

	\|}		\|}
		+
		+	[[Category:ME7]]

@@ Line 4: / Line 4: @@
-The MAF
+The MAF sensor output is sampled at 1 millisecond intervals. The sampled voltage value
 sensor output is sampled at 1 millisecond intervals. The sampled voltage value
 is first linearized using the 512 value characteristic curve MLHFM (which
 contains only positive values)&#8203;&#8203; for further calculation of mass
@@ Line 13: / Line 12: @@
-The
+The calculated air mass values &#8203;&#8203;are then summed in a memory segment.
 calculated air mass values &#8203;&#8203;are then summed in a memory segment.
 Once a segment is nearly full, the simple arithmetic average of the cumulative
 value over the last segment is calculated, i.e. it is divided by the number of
@@ Line 20: / Line 18: @@
-During idle
+During idle conditions, a selection is made between the measured air mass flow and the
 conditions, a selection is made between the measured air mass flow and the
 maximum possible air mass flow at this operating point, mldmx_w (taken at a
 height of -500 m and a temperature of -40°C) weighted by the multiplication
@@ Line 62: / Line 59: @@
-<u>Pre-assignment
+<u>Pre-assignment of the Parameters</u>
 of the Parameters</u>
-−
 CWHFMPUKL1 = 1
 CWHFMPUKL2 = 1
 FLBKPUHFM = 0.5
 FNWUEPUHFM = 0.5
 KFKHFM = 1.0
 KFPU = 1.0
 KFPUKLP1 = 1.0
 KFPUKLP12 = 1.0
 KFPUKLP2 = 1.0
 MLHFM = MAF sensor curve
-MLMIN = -200
+MLMIN = -200 kg/h
 kg/h
-−
-MLOFS =
+MLOFS = 200 kg/h
 kg/h
 PUKANS = 1.0
 PUKANS =
 .0
 <u>Application Procedure</u>
-. Determine,
+. Determine, input and review the MAF sensor linearization curve
 input and review the MAF sensor linearization curve
@@ Line 185: / Line 163: @@
-PUKANS = Ö(T<sub>0</sub>/T<sub>ANS</sub>)
+PUKANS = (T<sub>0</sub>/T<sub>ANS</sub>)<sup>0.5</sup>)
 where T<sub>0</sub> and T<sub>ANS</sub> are absolute temperatures (i.e. in
 Kelvin)

@@ Line 26: / Line 26: @@
 factor FKMSHFM. By this measure, short circuiting of U<sub>bat</sub> output to
 the engine can be prevented. [See module DHFM 63.130 Diagnosis: MAF sensor
-signal plausibility check:'' “With the HFM5
+signal plausibility check: ''“With the HFM5 sensor, if the battery voltage is less than 11 V , no more information about the plausibility of the HFM signal is possible (basis: voltage levels of
 sensor, if the battery voltage is less than 11 V , no more information about
 the plausibility of the HFM signal is possible (basis: voltage levels of
 .5-2.0 V cause a short circuit between U<sub>bat</sub> and U<sub>ref</sub>)...”'']