We have an RVDT R30D used to measure small angular displacements during deformation of ceramic samples. The RVDT suddenly stopped working. We confirmed that the input voltage was correct, and the cabling/connections are all secure. Any suggestions as to what would cause it to stop working?
Hello @dillm004
Welcome to the TechForum
when you say the R30D has stopped working, is it not showing on the device it is connected to or is there no signal on the white/output wire.
The output from the white wire is around 0.3 volts and does not react to any rotations. It does drop to 0 if we turn off the input power supply.
Greetings,
A device of the type has some internal electronics to do its magic, and like most such things they can be damaged by electrical stresses outside the indicated range. Static discharge is a famed culprit, though a power supply that over-shoots or gets polarity-swapped for some reason is another possibility. Damage from an output short circuit is possible, though most folks have gotten pretty good about including protections against such things these days.
How does the device’s current consumption measure relative to the 25mA figure mentioned in the datasheet? Either substantially higher or lower would be good indicators of device damage, though such a symptom is not necessarily guaranteed to show up.
If one has double-checked the connections, verified proper power supply voltage and measurement settings and otherwise ruled out silly mistakes of that sort (which are very common…) one can conclude that the sensor itself is indeed misbehaving, and start looking for contextual clues around the event that might give clues as to a cause. It’s quite uncommon for devices of the type to simply fail of their own accord without cause, so any available information about the before/after story would be useful to consider.
As for power supply problems, it’s not a silly idea to use an o-scope to watch what happens during the turn-on process. Some years back I was talking to a fellow who had a $3K inertial sensor on the end of a long cable go poof, because the supply went a bit too high for a few milliseconds when the switch was flipped. Things looked fine on a multimeter, but the 'scope told a different story…