False measurements are when the device shows a measurement while not being in contact with a component. The device will stop showing a measurement value when the tips are removed. False measurements will cause the device to continue displaying a measurement and not turn off, leading to the battery being drained.
There are a few reasons as to why the device is showing a false measurement. This could include the tips being misaligned or shifted during transportation or if the device has been dropped or mishandled. Replacing the tips with a new set may also cause false readings. Generally, these false measurements are caused by metal or plastic debris caught between the tips and arms of the device and can be fixed with these easy steps:
Start by removing the tips and cleaning the arms with isopropyl and a soft cloth or gauze to remove any extra debris. Reinstall the tips to the device. If the device is still showing a reading, remove the tips and continue to step two.
Try removing any excess flex cable from in or around the screw-holes. Gently rotate a drill bit by hand or use a Philips head screwdriver that is twice the size of the hole. This will scrape away any extra plastic and gold from the flex cable. The red circles in the image below shows where interference can occur.
Sometimes bits of metal remain stuck in the threads from assembly. These bits can be removed using a tap or one of the screws to clear the threads. Tighten and remove a few times.
Cleaning the screws may also help. Sometimes debris can be stuck between the threads.
If all else fails, make sure there is no metal bits stuck under the flex cable around the screw holes. Very rarely does metal get between these two pieces, but it can create false measurements. Always try scraping away extra flex cable first. Use sharp tweezers to remove any visible metal pieces without tearing or damaging the flex cable.
NOTE:Removing the flex cable will damage the glue and may cause issues when re-adhering the flex cable which can impact the accuracy of the measurements.
Make sure to clean away any residual plastic or metal using isopropyl and a soft cloth or gauze before reinstalling the tips.
Siborg has been working over the past year with the Institute of Automation and Electrometry at the Russian Academy of Sciences in creating a Calibration Fixture that will allow periodic calibration of all models of Smart Tweezers, and, most importantly, the LCR-Reader. The calibration fixture was then sent to Navair Technologies in Toronto, Canada to be verified. With this verification from Navair, Siborg will soon be able to include calibration certificates with LCR-Reader, which was a main hindrance in companies using the device.
The calibration unit utilizes a 4-wire connection which has been found to reduce noise between connections and the PCB within the calibration fixture.
Previous calibration fixtures used a 2-wire connector which worked well for older models of Smart Tweezers, including the ST-1, ST-2 and ST-3. The 2-wire connector was not able to handle the measurements within the LCR-Reader and Smart Tweezers measurement ranges. Due to parasitics, it could not measure lower values of capacitance and inductance and higher values of resistance. Therefore, the 2-wire calibration fixture was only able to measure mid-range values.
The calibration fixture uses 14 known components that lay within the range of measurements. When a device is connected, the fixture will signal a different component with each button push. The measurement values are instantly displayed on the LCR-Reader or Smart Tweezers‘ display which can then be compared to the known values of the components to determine accuracy.
“The new fixture makes it much easier to provide periodic traceable calibration now that it has been certified by Navair Technologies. We have now completed two versions of the calibration fixture using both 4-wire and 2-wire connections. The 4-wire is best suited for newer models, including the recent LCR-Reader. The 2-wire is best for the older models, including the ST-1, ST-2, ST-3 and STIC. These older models used a 2-wire connection in the handles of the device and could not be properly tested with the 4-wire terminal. This new calibration unit will allow all models to be tested and calibrated.” says the Director of Research and Development at Siborg, Michael Obrecht.
Soon, the calibration certificates will be available in the LCR-Reader Store; there will be 2 types to choose from: a basic calibration certificate that ensures the device has been calibrated, or a more detailed format that shows the measurement results compared to the known values.
A new optional replacement tip has been made available. This new design is more ergonomic than the straight-tip models by angling down toward a component or PCB, making it easier to hold the LCR-Reader or Smart Tweezers device at a more horizontal level. All devices will still be equipped with straight-tips, with the bent-tip an additional purchase.
Siborg Systems Inc and the Institute of Automation and Electrometry at the Academy of Sciences have banded together in creating new calibration jigs with 4 and 2 wire connections allowing for all models of Smart Tweezers and LCR-Reader to be calibrated.
This jig cannot create NIST certificates and needs to be certified itself, but is a helpful tool for periodically checking the accuracy of devices as well as troubleshooting if a device should fail or malfunction.
When connected to a Smart Tweezers or LCR-Reader device, one press of the button allows the calibration jig to systematically cycle through 14 known components. The results are then displayed on the ST or LCR-Reader display to be compared to the known values.
The 4-wire jig is compatible with models from ST-3 and up, including the LCR-Reader, while the 2-wire jig is best for older models.
Since the LCR-Reader does not come with an NIST traceable certificate, Siborg sent 4 randomly chosen LCR-Readers to Toronto’s Navair Technologies, one of the leading calibration facilities in Canada that offers NIST certification.
Siborg has recieved the results and they provided surprising results. Siborg has claimed that the LCR-Reader offers a 1% basic accuracy, while the results are closer to 0.5%. The only measurement that was away from the estimated values was the 1 Ω measurement which is off due to parasitics between the tips.
Siborg Systems Inc. has released a new LCR-Reader and Smart Tweezers LCR-meter Maintenance video. The video demonstrates how users can replace the screen, flex cable, battery and tips. This will allow users to replace key components on the device themselves without having to send the device back to their distributor or Canada for maintenance.