Study for the Amtrak Signal Maintenance Training – Level 1 (SMT-1) Test. Our materials include multiple choice questions and detailed explanations to help you succeed. Be prepared for your exam!

Multiple Choice

Which color indicates DC normal voltage?

Color-coded indicators on DC power panels are used so you can spot status at a glance. Green is used to signal normal operation, meaning the DC voltage is within its expected range and the equipment is ready and safe to operate. The other colors represent non-normal conditions—red usually means a fault or dangerous condition requiring immediate action, yellow indicates caution or a degraded state that should be checked, and blue is often used for a nonstandard or special condition depending on the panel. So green is the color that best matches DC normal voltage.

Color-coded indicators on DC power panels are used so you can spot status at a glance. Green is used to signal normal operation, meaning the DC voltage is within its expected range and the equipment is ready and safe to operate. The other colors represent non-normal conditions—red usually means a fault or dangerous condition requiring immediate action, yellow indicates caution or a degraded state that should be checked, and blue is often used for a nonstandard or special condition depending on the panel. So green is the color that best matches DC normal voltage.