AZT-9
ZPrAE Sp. z o.o.
5
less than 250 ms. "Cold start” (discharged energy storage) requires additional time (ca.
40 s) to charge energy storage before initiation of the shut off impulse.
3.1. Current inputs.
The current inputs module is divided into two sections: the measurement section
with measuring current transformers and precise analogue-to-digital converters, and the
power supply section with current transformers supplying power to the device.
Fig. 3.1. Current circuits.
Fig. 3.2. Current circuits in a protection device fitted with a test module.
3.2. Shut off circuits.
To send shut off impulse the AZT-9 uses energy stored in twin energy storage.
Combined with independent power supply from current circuits (powering the protection
device, as well as charging the energy storage) this allows for operation of the protection
even in case of complete lack of auxiliary power supply. The recommended setup consists
of two switch off circuits working with a separate third switch off coil. However, shut off
circuits sending impulses to CW1 or CW2 coils can be installed. That case requires all
activation impulses to be separated with depletion diodes. Since the protection device has
two energy storages and two shut off impulse outputs the energy can be increased, double
tripping pulse (re-trip) is possible or impulses can be sent to two independent circuit
breakers.
