AZT-9
8
ZPrAE Sp. z o.o.
contact outputs:
-
AZT working / AZT defective,
-
AZT energized / AZT unenergized,
and binary inputs:
-
shut off lock (if voltage is connected the AZT will not send shut off impulses),
-
external energize signal P
BFP
(e.g. by a breaker failure protection or the
transformer's temperature breaker)
The last function acts as a local breaker failure protection of the specific feeder.
Sending shut off impulses from primary protection and elapse of delay time t
BFP
if the I
BFP
criterion is met will cause the AZT-9 protection device to operate and send a shut off
impulse from energy storage. This can be compared to the so called re-trip of breaker
failure protection circuits.
Fig. 3.7. Auxiliary power supply, contact outputs and binary inputs.
To expand capabilities of the AZT-9 protection device beyond the basic functions
additional AD1 input card and YZ1 output card have to be added. However, they need
auxiliary power supply to work. Both the inputs and the outputs can be configured with the
software supplied with the AZT-9.
An optional MZD-1 card provides the possibility of connecting additional power
supply to the device; it allows the device to be powered from circuits of voltage relays.
Fig. 3.8. Additional auxiliary power supply.
