J.P. Instruments EDM 930 Primary Primary Installation Manual User Manual
Page 28

FAA Approved Installation Manual for the
Report No 908
EDM-900 and EDM-930
Page 28 of 50 Rev J
Primary Engine Data Management System Date 5-24-14
Manifold Pressure Calibration
The manifold pressure must be calibrated to the ambient air pressure. Enter the current ambient barometric
pressure. The engine must not be running. This setting is not the same as the altimeter setting that you receive
from ATIS or Unicom. It will vary with field elevation. Use the chart below to calculate the MP FACTOR. Multiply this
MP FACTOR by the altimeter setting that you receive from ATIS or Unicom. For example if the field elevation is
1700 ft and the altimeter setting is 30.1, the MP FACTOR is 0.9400 from the table. Multiply 30.1 x 0.9400 to get the
ambient MP of 28.29.
Field
Elev.
MP
FACTOR
-500 1.0182
-400 1.0145
-300 1.0109
-200 1.0073
-100 1.0036
0 1.0000
100 0.9964
200 0.9928
300 0.9892
400 0.9856
500 0.9821
600 0.9785
700 0.9750
800 0.9714
900 0.9679
1000 0.9644
1100 0.9609
1200 0.9574
1300 0.9539
1400 0..4
1500 0.9469
1600 0.9435
1700 0.9400
1800 0.9366
1900 0.9332
2000 0.9298
2100 0.9264
2200 0.9230
2300 0.9196
2400 0.9162
2500 0.9129
2600 0.9095
2700 0.9062
2800 0.9028
2900 0.8995
3000 0.8962
3100 0.8929
3200 0.8896
3300 0.8863
3400 0.8830
3500 0.8798
3600 0.8765
3700 0.8733
3800 0.8700
3900 0.8668
4000 0.8636
4100 0.8604
4200 0.8572
4300 0.8540
4400 0.8508
4500 0.8477
4600 0.8445
4700 0.8414
4800 0.8382
4900 0.8351
5000 0.8320
5100 0.8289
5200 0.8258
5300 0.8227
5400 0.8196
5500 0.8165
5600 0.8135
5700 0.8104
5800 0.8074
5900 0.8043
6000 0.8013
6100 0.7983
6200 0.7953
6300 0.7923
6400 0.7893
6500 0.7863
6600 0.7833
6700 0.7804
26. RPM Sensor installation
Use the J3 connector harness 790422 and connect the 3 leads using the supplied 3-pin connector and pins. There are
four types of magnetos commonly in use. You must have the correct RPM sensor for the magneto installed in the
aircraft. The following part numbers apply: Slick – pressurized 4000, -6000 series use JPI P/N 420809. For the Bendix
pressurized -1200 series use P/N 420807. Dual magnetos use JPI PN 420808. For the Bendix -20 series and Slick
600 use JPI P/N 420806. Mount the sensor as shown in the appropriate diagram below. Note: this is eligible for
installation on all 4 & 6 cylinder engines only.
.