Table of Contents
National Instruments SCXI modules
- System fails to acquire data or values reported are "off"
Reset the SCXI-1001 Chassis using Measurement & Automation Explorer (MAX) as described below.
- Double-click Measurement & Automation Explorer (MAX) icon on the desktop.
- Expand "Devices and Interfaces" by left-clicking the + symbol. You should see SCXI-1001 name and number in the list.
- Right-click and select "Reset chassis".
- Now try, running the LabVIEW GUI. If problem persists, power cycle the chassis and reset it again following the steps described above.
Note: If the device does not show up in the list or still reports wrong values, refer to the National Instruments website ni.com/support for more troubleshooting tips.
IMPORTANT: Resetting the SCXI-1001 chassis can sometime change the configurations for the TC-2095 rack, making the muffler temperature max out at 300 degree F. If this occurs, simply follow the steps below to resolve the issue.
- Temperature readings are "off"
Verify that the thermocouples are connected to the right channels on the extension box as well as on the TC-2095. See Operating Procedures
- Analog voltage readings are "off"
If this is the case for the LM-2 kit used for AFR/Lamda measurements, please read below. For all other sensors, check your connections and reset the SCXI-1001 chassis. If problem persists, refer to the user manual for the corresponding equipment.
- Muffler temperature maxes out at 300 degree F
In LabVIEW, change the DAQ configurations for expected thermocouple voltage output from 100 mV to 2500 mV following the procedures below:
- Open the block diagram from LabVIEW GUI, by pressing Ctrl+E
- Double-click on "DAQ Assistant" block to edit the DAQ configurations.
- For all thermocouple channels, set the expected range to 2.5k.
- Click "OK" to save and exit DAQ Assistant.
NOTE: The BNC/TC-2095 are connected to the SCXI-1102C module. Because of the 2 Hz bandwidth of the SCXI-1102 module input channels, after changing the gains you must wait approximately 3 s for the channels settle in order to get an accurate measurement.
LM-2 Digital Meter / Oxygen Sensor
IMPORTANT: If the AFR/lambda value reported on LabVIEW GUI does NOT match the value on LCD on the LM-2 Digital Meter when the engine is not running, this is normal. Only inconsistent readings when the engine is running should be addressed.
Ensure that the USB cable AND the power cable are connected when taking measurements.
- The LCD on the LM-2 Digital Meter is dim or no valid readings on LabVIEW GUI
Check all power connections. Make sure the USB cable is connected to a USB port on the PC and the power cable/adapter is correctly connected. If using a cigarette adapter, ensure that the adapter has a min. of 1 A (1000 mA) current rating.
Dim LCD indicates that the LM-2 Digital Meter is only powered by USB cable. When the power cable is connected, the LCD should be fully lit.
- Inconsistent reading.
Check all power connections. Ensure that the USB cable AND the power cable are connected when taking measurements. The LM-2 Digital Meter MUST be connected to USB cable and power cable at the same time to get valid readings when the engine is running.
If problem persists and the reported AFR values on LabVIEW are offset, follow manual instructions to reconfigure the analog out 1 channel on the LM-2 Digital Meter. The default should work. Note that the voltage measured by LabVIEW is indicated on "Analysis" tab on the LabVIEW GUI.
TFX Software / Pressure Transducers / Charge Amplifiers
Check all connections. If using the KISTLER Charge Amplifier, ensure that it is set to OPERATE MODE to acquire data. Verify that values in the engine spec file, matches with settings on the amplifier. Also, refer to user manuals for the TFX, KISTLER and PCB sensor kit.
Load Cell / Encoder from Dyn-Loc IV Controller
Check all connections. From load cell to MS connector to Dyn-Loc IV controller. Examine the 60-teeth trigger wheel on the back of the DC motor. Also, refer to Dyn-Loc IV controller user manual for error codes and procedures for calibrating the load cell.
Software: LabVIEW/MATLAB Script
- Notes in 'Observation' tab in LabVIEW GUI are not saved
Simply use the blue 'Stop Acquisition' button to terminate the data acquisition, instead of the 'red' button on LabVIEW toolbar. The button color should change from blue to red. Note that there's small delay, after activation of this button, required to log observation note.
- Error running MATLAB script
Refer to comments in the script for how to correctly use the program.
IMPORTANT:At most two CSV files, can be compared at the same time.