Hürriyet, Kartal

Hürriyet is one of the Kartal neighbourhoods dense with mid-age apartment stock, and the most insidious fault here is a main neutral terminal loosening downstream of the meter. As neutral resistance rises, the voltage on one phase climbs above 250 volts while another falls to 180; the result is a television, modem, boiler board and refrigerator board all failing on the same night. Customers assume a grid fault, yet the problem is inside the building and is easily proven by measurement.

The repair opens every neutral connection downstream of the meter, cleans oxidised surfaces with dielectric solvent and torques the terminals to the manufacturer's figure. An over/undervoltage protection relay and a Type 2 surge arrester are added to the main board so appliances survive the next neutral loss. At the end, voltage on all three phases is read again under load and the balanced values written onto the service report and handed to the building management.

The most frequent call in Hürriyet is a residual current device that trips again the instant it is reset. The technician disconnects every branch at the board and resets the device; if it holds the fault is in the installation, if not the device itself has failed. Branches are energised one at a time until the offending leg is certain, and that leg is measured with a 500 V megohmmeter. This separates leakage from a damp bathroom junction box, a charred kitchen terminal or a defective appliance.

Inverter air conditioners, induction hobs and LED drivers generate high frequency harmonics that trip a standard Type AC device for no apparent reason; in those flats it is replaced with a Type A or a harmonic-immune Type F unit. At Hürriyet addresses a single 30 mA device commonly protects the whole flat, so lighting, sockets and wet rooms are split onto separate devices. After installation the trip time is measured in milliseconds with a dedicated tester and written onto the service report.

In the older stock of Hürriyet a ceramic screw-in fuse board still sits in the hall cupboard. These boards contain no residual current device at all, so protection against electric shock is zero; the fuse melts and welds into its base under overload, fails to clear a short circuit and the body carbonises over time. The sockets usually have no earth either, with the neutral pin bridged to the earth terminal.

The old board is removed entirely and a flame-retardant modular DIN-rail enclosure installed: an independent Type C breaker per room, dedicated circuits for kitchen and bathroom, and a 30 mA Type A residual current device plus a Type 2 surge arrester at the intake. Flat sub-boards use a minimum 6kA breaking capacity and building intakes 10kA. Where a Hürriyet address has no earth, a solid copper electrode is driven, its resistance measured with a digital earth tester and the socket jumpers removed one by one.