File:Detector-comparator-diff.png

Summary
Comparator output (top of the image) of a detector rail for different minecarts. Only the minecart with chest (which holds 12 full stacks) and the minecart with hopper (which holds 3 full stacks) give a signal from the comparator. All types of cart cause the detector rail to give power to the adjacent redstone dust (bottom of the image).

Shown from left to right:
 * No cart
 * Minecart with Chest
 * Minecart with Hopper
 * Simple Minecart
 * Minecart with TNT
 * Minecart with Furnace

Version 1.8.1 vanilla.