A designer is selecting an LED driver for an outdoor display exposed to dust and rain. Which specification should be examined first to determine whether the driver can withstand these environmental conditions?
Ingress Protection (IP) rating
For any equipment installed outdoors and exposed to dust and rain, the first question is whether its enclosure can keep those elements out. This is precisely what the Ingress Protection (IP) rating quantifies, so it must be examined first when selecting an LED driver for such a location.
An IP rating is written as IP followed by two digits, IP[X][Y]:
For an outdoor display facing dust and rain, a driver of at least IP65 (dust-tight and protected against water jets) is generally required so the environment cannot damage the electronics.
The other specifications matter for performance but not for survival in the environment: dimming compatibility concerns brightness control, power factor rating concerns how efficiently the driver draws current from the mains, and output current tolerance concerns how accurately it drives the LEDs. All of these are irrelevant if moisture or dust destroys the driver first, which is why the IP rating is the primary environmental check.
During insulation testing of a long underground cable, a technician observes higher leakage current compared to a shorter cable of the same type. What is the most likely reason?
A stone is thrown horizontally from the top of a 20 m high building with a speed of 12 m/s. It hits the ground at a distance R from the building. Taking g = 10 m/s2 and neglecting air resistance will give :
A mass is attached to a spring that hangs vertically. The extension produced in the spring is 6 cm on Earth. The acceleration due to gravity on the surface of the Moon is one-sixth of its value on the surface of the Earth. The extension of the spring on the Moon would be:
Directions: Each item in this section consists of a sentence with an underlined word followed by four words (a), (b), (c), and (d). Select the option that is opposite in meaning to the underlined word and mark your response in your Answer Sheet accordingly.
The major source of vitamins and minerals for vegetarians is
Which of the following statements about the Deccan Riots Commission is/are correct?
1. The Commission did not hold enquiries in the districts which were not affected.
2. The Commission did record the statements of ryots, sahukars and eye-witnesses.
Select the correct answer using the code given below: