ORIGINAL: Gremlin Castle
Units such as the I-4C product give an exact system voltage reading accurate to .01 of a volt. They show the system and the draw of each surface as it is actuated. If you care to, you can add additional mechanical load to a surface with you fingers and see what that load looks like. It gives a dynamic picture of the system versus a fixed reading found on an ESV. I use the Futaba voltage checker on some of my planes and onboard voltage indicators on others. Since neither is a potential point of failure during flight it comes down to whether the use of either is an added step of diligence or just a ritual that gives us a little more confidence before flight.
ORIGINAL: mglavin
Gremlin,
The simple fact is these devices cannot or do not display the actual voltage under static loads and or whilst stirring the sticks, as I eluded to. Granted this information is better than nothing... The response time, sensitivity and graphical representation of these devices are lacking for our purposes IMO.
I feel the loaded voltage via an ESV is a much better indicator for our needs, simply because we can view numerically the actual system voltage verses a loosely calibrated graphical display range and sustain the load indefinitely if so desired, this provides an indication of the batteries current potential under load. Which again is not necessarily the best method, but is a field performable means to an end after and or prior to flight.
FWIW: The current loading ESV’s work exactly like the i4c’s digital volt meter if you please and they are capable of loading the battery too (not sure about Futaba's). Simply stir the sticks for a dynamic load reading or engage the load(s) for indefinite user selectable battery loading/testing. ESV’s devices do NOT provide a fixed system reading as noted above, they are capable of displaying actual system voltage in real time. In fact you can even engage a load and stir the sticks simultaneously for a loaded dynamic voltage reading… I have used and use the i4c meter in several GS models for many years, excellent products… Additionally I have tested and performed R&D with the Voltwatch and similar type products, while the work and many are happy with same as I mentioned previously I find them inadequate or lacking for our needs. But again they are better than nothing.