A Motion Encoder Cart fails to record any motion when used with a Vernier Motion Encoder System (VDS-EC, discontinued).

Troubleshooting is easiest if you have multiple Encoder Carts.

  1. Find a receiver and cart and track that do work together. Note how the blue light flickers on the receiver when the cart is in motion. On this system, you know that the track and the receiver are working, and that the software is correctly configured.
  2. Put fresh batteries in the suspect cart and place it on the track. Turn it on and position it with the blue light facing the receiver.
  3. Start about 50 cm from the receiver. Move the cart. Does the receiver flicker blue light and does the software record the motion? If the receiver remains dark, and the software position reading is unchanged, yet the cart is clearly turned on, then the cart is not transmitting and must be repaired. Contact Vernier Technical Support.

If you do not have multiple working carts and receivers, here are some things to check:

  • Are the encoder strip on the track, the encoder bar label on the cart, and the bar label on the receiver all on the same side of the center groove? They must be in a line for the cart to work.
  • Does the cart have fresh batteries? Is the cart turned on with the blue light facing the receiver?
  • If using a 2 m track, is the cart set to the 2 m mode? See the switch inside the battery compartment.
  • Is the software set up for the Motion Encoder? LabQuest App 2.3.1 or newer (for original LabQuest 1.7.1 or newer), and Logger Pro or newer is required. If using Logger Pro with a LabPro, you must connect to DIG/SONIC 1 and open the file found in Probes and Sensors>Motion Encoder System.
  • Check to see if the blue light on the receiver flickers when the cart is moved.

If all of the above is confirmed, yet the blue light does not flicker, either the cart or receiver is bad. You cannot tell which without additional hardware. Contact Vernier Technical Support for assistance.

See also:
Motion Encoder System Troubleshooting and FAQs
Encoder Cart only reads to about 10 cm.