The health directorate advises people to avoid working in sunlight for a long period, but rest is a luxury the poor cannot afford
The dead have been identified as Amena Begum, 55, her daughter-in-law Shirin Akter, 30, and Akter's daughter Afreen.
They were brought to Dhaka Medical College Hospital where the doctors declared them dead around 11:30am on Monday, said DMCH police camp's Sub-Inspector Bachchu Mia.
The power cable snapped round 10:30am amid heavy rains in the capital since morning, said Police Inspector Md Hafizur Rahman of Chawkbazar.
Locals rushed five of the family to hospital, where three were declared dead while two others are being treated.