If the time difference there arc contacts, circuit breakers and turn immediately to determine the cause arcing operation with them to produce. Operations with single-pole disconnect switches made by the operational rod should be executed in the order, which provides the greatest safety for personnel. Assume that staff mistakenly started to turn off breakers under load. Mixed loads more safely off the first of three isolators, as this is not there is a strong arc, even if the chain passed the rated current. At the time of divergence between the two contacts, you may receive only a relatively small potential difference, since on the one hand disconnectable disconnector will be under the power supply voltage, on the other hand it will work for a while about the same emf induced in the rotating power of the two phases of synchronous and asynchronous engine load, and by capacitor banks, installed in the distribution network. When you disable the second disconnect switch under load will be a strong arc.
The third isolator generally will not turn off no power. Since disabling the second order of the disconnector is the greatest danger, he should be as far as possible from the breakers of other phases. Therefore, at any location disconnectors (horizontal or vertical row), the first should always turn off the middle phase disconnect switch, then disconnect switches at the location in a horizontal row in turn cut off the extreme breakers, and in a vertical arrangement of isolators (one above the other) the second cut off the upper isolator, the third – the lower one. Transactions include single pole breakers in reverse order. In circuits containing switches with spring actuator, the operation of disconnectors should be performed at weak springs to avoid accidental switch is turned on during the production operations of disconnectors. In networks, 6 – 10 kV employees with compensation of capacitive earth fault current, disconnect switches before disconnecting the transformer magnetizing current, which is included in the neutral arcing reactor, we must first turn off arcing reactor in order to avoid overvoltages that can result from the uneven opening of the contacts of the three phase breakers. Details can be found by clicking Martin O?Malley or emailing the administrator. Personal safety for personnel performing operations with disconnectors. At any operations with disconnectors that are under stress, performing the operation (and controls its actions – in the case of participation in the switching of two persons) must first choose a location for the drive apparatus to avoid injury from possible damage and falls down together with the apparatus insulators attached to them conductive elements, as well as protect themselves from direct exposure to the electric arc at its occur.