PRODUCT INFORMATION
INDEX
DATE
Dep. 2
IO-G-M-33-002e F
May 2016
CONVENTIONAL SPARK PLUG REPLACEMENT CRITERIA IN
GAS ENGINES
2/3
The values set in the CPU-95 unit program for the engines to which this document applies are:
Energy level: E3
Minimum CAVG value: 90
Maximum CAVG value of the high voltage level in the secondary circuit: 130 (alarm on display: HI SPARK
VOLT).
Limit CAVG value setting for detecting an ignition failure in the secondary circuit: 135 (alarm on display: NO
SEC. SPARK).
Maximum CAVG-EAVG difference: 15
Maximum EAVG-CAVG difference: 15
The remaining values that refer to changes in energy levels are not necessary, since the system does not use
them.
4. USE OF THE GIS IGNITION UNIT DIAGNOSIS CAPABILITY
The GIS ignition unit has secondary voltage values (kV) which are used to determine if the spark plugs are
reaching the end of their service life. The secondary voltage value increases as the spark plug gap increases
and greater electric arc to generate the ignition spark is required.
The limit values may vary in different engines.
Fig. 1 - Secondary voltage values on the GIS ignition unit screen
5.2.28
O&M_2.002211.810_A_10_2016