KARACHI:
Appliances are blowing up all over Karachi because of violent voltage fluctuations. This is all linked to the precious neutral wire that acts as a protection against such fluctuations. The problem is that it is easy to access and cut because no current flows through it as such.
There have been reports that saboteurs linked to the Karachi Electric Supply Company (KESC) protest are cutting the neutral wire at night, especially in DHA and Clifton. In poorer neighbourhoods drug users often steal it to sell to scrap mongers. In other instances, it has grown so weak or damaged that it sags or drops to the ground. Either way, its absence means that high surges are destroying appliances all over these neighbourhoods.
Case study
Businesses along 26th street in Clifton Block 4 are a case study. The restaurants, gallery and café owners tried to tackle the fluctuation on their own.
Koel Café was forced to shut down for two days. On Saturday, at around 8:30 pm, fluctuations began at the restaurant, which was already running entirely on its generator for a week, said its manager. “I had a table of 16 people seated inside and the air conditioners stopped cooling and our light bulbs became so bright it seemed they would explode any minute,” she told The Express Tribune.
They switched their panels from KESC to their generator because there was major fluctuation when they relied on KESC. “Load shedding has been going on for ages on our block, but then for the past two weeks the voltage fluctuation started and one of our air conditioners burnt.”
On Saturday night, voltage fluctuation started to develop even on the generator, which provided the café 440 volts. “Once the fluctuation started with KESC, people from the area found their own solutions to the problem but we share neutral phases so it caused problems for us,” explained the manager. “Three or four days back, a neutral phase was hit and this caused fluctuation problems on the generator so we were forced to shut it off.”
According to restaurant owners, a van, which they believed was from KESC, came to fix the problem last week. When the men climbed the ladder to examine the wires, residents of Neelam Colony began stoning them and firing so they were forced to leave, said sources from one business. Down the road, the owner of Café Flo, Florence Villiers, faced similar problems. “We were running on a generator for 24 hours because we did not have light for five consecutive days last week,” she said.
The restaurant’s generator, which is 1,110 volts, only runs for 8 hours before it starts heating up. “It was also a bit of a disaster because I had to buy Rs26,000 worth of diesel every day,” Villiers grumbled.
Residents and art galleries also complained. “Ever since we came to 26th Street, there have been electric faults but the past two weeks have been the worst,” said Canvas Gallery’s accountant Omar Ali. “We cannot turn on the ACs, unless the generator is on because they burn out because of the heavy fluctuation.”
Hot wired
An expert, who only wanted his first name Hamid to be used, told The Express Tribune that KESC had discontinued the grounding or earthing system for every second electrical pole. This is also one possible reason why connected houses are suffering when their neutral wire is being cut or stolen. The earthing system immediately disconnects the supply if the neutral wire is affected. The ‘fuse-like’ connector would promptly switch off in the electric pole or pole-mounted transformer and the surge would not make it into the house.
Out of joint
A resident of Darakhshan Villas said that she had lodged repeated complaints at the KESC office but it has been 15 days. She claimed that someone had contacted her, saying they were from KESC and would do the repairs for Rs15,000 - jointing a dropped neutral wire. The heavy fluctuations have cost her a TV, deep freezer, split air-conditioner and internet device.
KESC’s explanation
A KESC engineer, who preferred to remain annonymous, told The Express Tribune,“KESC uses a three-phase, ‘star’ connection. The neutral wire is connected at the star-point, it is common to all three-phases and is grounded at the source. Grounding keeps the neutral at zero potential. As soon as it is cut, the star point starts ‘floating’ - the phases which are lightly loaded experience high voltage and the phases which are heavily loaded experience low voltage, this is how fluctuation is caused”.
with additional reporting by Husna Anwar
Published in The Express Tribune, June 15th, 2011.
COMMENTS (10)
Comments are moderated and generally will be posted if they are on-topic and not abusive.
For more information, please see our Comments FAQ