Why does my IN191 Blood FlowMeter show an output of -5 V on both channels?

When connecting a new flow probe to the Laser Doppler Blood FlowMeter and the readout on both the LDF and backscatter channels are -5 V, then the probe isn't recognized. Most likely you have purchased the probe separately or the probe was connected to a different unit before. You will need to calibrate the new probe to the Blood FlowMeter.

Please note, probes shipped with a Blood FlowMeter are factory calibrated and do not require further calibration.

The Blood FlowMeter is designed to be easily configured and calibrated for new probes. This operation requires a Calibration Kit  (purchase separately), which includes a controlled concentration of latex spheres in suspension. Please note that the calibration solution has a use by date. Please follow the instructions provided with the Calibration Kit as calibration of probes is not possible without it and should not be attempted.


For further technical assistance with this or any other issue, please contact ADInstruments Technical Support by clicking HERE.