Which bulb glows brighter?

Very important question:

Two bulbs of 40W and 60W are connected in series with an AC power supply of 100V. Which bulb will glow brighter and why?
Ans:
1. When connected in series: In a series connection, current flowing across each element is same. So when 40W bulb and 60W bulb are connected in series, same current will flow through them. To find which bulb will glow brighter we need to find the power dissipation across each of them. From the relation
P=(I*I) R
since current is same we can say that power dissipation will be higher for the bulb with higher resistance i.e. 40W bulb.
Hence 40W bulb will glow brighter in series connection.
2. When connected in parallel: In a parallel connection, voltage across each element is same. So when 40W bulb and 60W bulb are connected in parallel, voltage across them will be same (100 V in the given case). To find which bulb will glow brighter we need to find the power dissipation across each of them. From the relation
P=(V*V)/R
since voltage is same we can say that power dissipation will be higher for the bulb with lower resistance i.e. 60W bulb.
Hence 60W bulb will glow brighter in parallel connection.
NOW HOW TO REMEMBER THIS-
***At our homes, loads (such as bulbs) are connected in parallel and you always see that higher rated bulb glows more brightly i.e 100W bulb glows more brightly than 60W bulb or 40W bulb.
***So always remember if bulbs are connected in parallel, the bulb with higher rated power will glow brighter and if they are connected in series, the bulb with lower rated power will glow brighter.

Limit Switches

Limit switches
Trustworthy detection devices
Limit switches are electro-mechanical devices. The contacts are mechanically linked to an actuator. By combining different types of actuators, casings and contacts, our limit switches are perfectly suited to a large variety of applications whatever the environment.

Main benefits

Reliable operations
Visible operations
Each application gets the right limit switch.
Main features

Plastic or metal casing, IP65 or IP67
Able to switch strong current up to 10 A
Mechanical durability up to 10 millions of operations.

Reclosers

MV outdoor vacuum reclosers
Single and three phase reclosers up to 38 kV, 16 kA and 1250 A for outdoor pole mount or substation installation.
Reclosers are predominantly located on the distribution feeder, though as the continuous and interrupting current ratings increase, they are seen in substations, where traditionally a circuit breaker would be located. Reclosers have two basic functions on the distribution system: reliability and overcurrent protection.



Why RECLOSERS?

Increased reliability - the highest creep distance among the recloser poles on the market ensures long-term performance in any environment
Unparalleled performance - the HCEP (Hydrophobic Cycloaliphatic Epoxy) material of the poles provides the best insulation for outdoor use, shedding water and debris, thus reducing the probability of flashovers even in heavily polluted areas
Simple, fast and safe maintenance as all the electronics are in the low voltage unit, eliminating the need for a bucket truck to isolate potentials to service electronics
Easy integration with multiple controller options, including the PCD, RER615, RER620 and SEL-651R, to accommodate any grid modernization application.