Measuring with LVDTs without mains power

[bae_simon]

Are there any data acquisition solutions to drive and record from LVDT's that do not need 240V power i.e. SCXI chassis. The measurement system will go inside a large machine tool with flood coolant so 240V live power is not good. Ideally I would like to use a USB bus powered system so it is plug and play and low voltage. The measured items are moved on a pallet shuffle system, so the wiring either power or sensors must be unplugged easily.

Or are the any precision linear distance devices similar to LVDTs which can be used with a NI USB DAQ system. There are to record any physical movement of a component in process. Resolution 10 microns and sealed against water and swarf.

Regards

Simon

[Logan_K]

The SCXI-1000DC Chassis is powered off a DC power source of 9.5V - 16V (5.5A). Then you will need a computer to acquire the data, so with the SCXI-1600 module you can connect the chassis to the computer via USB.

-Logan K

[Henrik_Volkers]

Schaevitz makes LVDTs with build in decoders and analog output

for example here http://www.althen.de/uploads/pdf_catalog/displacement_and_position/P104_EN04.pdf

5V supply

[Conseils]

What you might wish to consider is using an FM system and a transformer to isolate the signal from the system.

If you use a carrier based system (FM) then you will obtain a high degree of noise immunity and by using a transformer you will obtain safety isolation and protection to a required international standard.

Lucas Schaevitz manufacture a conditioning module that meets the above requirements and I believe that Solatron do as well.

I have used both of these manufacturers equiment for many years and found both to deliver excellent products.

LVDT's don't last for ever so try to accomodate the life of the item (the bearings wear out eventually and coolant is horrible stuff even in these days of highly filtered coolant).