electrogearhead
Electrical
- Oct 8, 2009
- 1
I would like to know more information about Siemens piezo common rail diesel injector operation. What I do know is the injectors are operated by a controlled high voltage pulse to the piezo stack that controls a small valve that in turn controls the injection delivery. The piezo stacks are polarity sensitive, expanding or contracting with applied high voltage signal. Typically a piezo may be damaged if greater than 20% reverse voltage is applied.
How could an engine run if the polarity was incorrect? Checking the injectors on flow bench proved they were were damaged, some stuck closed another stuck open. I am thinking the incorrect piezo operation bounced the control valves enough to pass fuel. The engine was unloaded and at near idle conditions.
How could an engine run if the polarity was incorrect? Checking the injectors on flow bench proved they were were damaged, some stuck closed another stuck open. I am thinking the incorrect piezo operation bounced the control valves enough to pass fuel. The engine was unloaded and at near idle conditions.
