Encoder Monitoring via wireless

I have an application where a customer wants to measure the position of the spreader on a gantry crane for tracking/logging. The spreader being the part that is raised/lowered to snatch the object needing to be raised/lower.

For all intensive purposes, lets say the only way to measure the distance the spreader has been lowered/raised, is to attach an ENCODER on the cable drum.
Also, this crane is mounted on rails for it to shuttle itself up/down the factory floor transporting the load.

The encoder will need to be monitored by a PLC. One theory was to connect the ethernet encoder to a wireless Bluetooth Bridge like a Wago or Anybus, and bridge it back to the network where the PLC doing the tracking resides.

Has anyone ever done this, or have any suggestions? Is this even feasible over a Bluetooth bridge....or, even a WIFI bridge?

I am not looking for a huge update rate nor do any type of control from the encoder. Again, this is strictly for tracking/logging of the spreader.

FYI - The crane control system I am not allowed to access. The encoder and bridge would be a separate system attached to the crane.

Googled “Wireless Encoder”

http://www.beisensors.com/wireless-encoders-swiftcomm.html

May be too much for what you’re wanting to do.
Keep it somewhat simple.

Does it HAVE to be an encoder? Plenty of laser measuring sensors out there with analog output. Unless there is heat or steam in the lasers path, it should work fine. Balluf makes a good one and SICK does too. Banner was hit and miss.

Just about anyone does analog in some flavor of wireless. Cheaper I’m sure too.

Not fully sure but this could be solution:

http://www.arck-sensor.com/products/steel/sirrah/ls08

Also in this case you have feed power to the spreader to power up transmitter

I've seen leaky coax solutions used for gantries/cranes before. Essentially, there is a long coax cable used, laid along one of the troughs, with slits cut in it at a regular pattern to allow wifi frequencies to escape, with a small antenna that runs along it tied to the gantry. I've used it paired with Siemens access points for profinet control, even profisafe safety IO. I've seen update rates as low as 32ms.

It isn't cheap, though, and as you said you don't need a fast update rate for logging.

Wi-Fi encoders with 10 year life time battery

http://www.hohner-elektrotechnik.de/en/products/wireless-encoders.php