Photogate (VPG-BTD)
Specifications and User Guide


  • Primary Test: Is the shutter positioned properly? A mechanical shutter is used to block the internal gate, switching the device to laser gate mode.
  • Secondary Test: Connect the Photogate to an interface and start the data-collection program. Confirm that the Photogate has been identified by the program, and then use your hand to block and unblock the gate to confirm that the Photogate is working.
  • If the Photogate is not working with your Picket Fence, make sure that the protective plastic covering the picket fence has been removed.

If you are new to Photogates, we have three informative guides to help you get started. Choose the guide that matches the software you are using:

Using Logger Pro on a computer:
Logger Pro – Introduction to the Vernier Photogate

Using LabQuest App:
LabQuest – Introduction to the Vernier Photogate

Using Graphical Analysis:
How do I set up wired Vernier Photogates (VPG-BTD) for data collection using Graphical Analysis and Graphical Analysis Pro?


Vernier Photogate with Picket Fence:

-new order code: VPG-BTD
-old order code: VPG-DG (ULI only)
-Power requirements: 5 VDC at 40 mA
-Infrared source: Peak at 880 nm
-Output is high and LED off for unblocked gate
-Output is low and LED on for blocked gate

It is not necessary to calibrate this sensor.

Ultra Pulley Attachment (SPA)
Picket Fence (PF)
Bar Tape (TAPE)
Laser Pointer (LASER)
Laser Pointer Stand (STAND)

For information regarding the Go Direct® Photogate (GDX-VPG), see
Go Direct Photogate Troubleshooting and FAQs