VULCANIC 30252.01 Operating Instructions Manual page 50

CS2 R30252.xx
from 75A to 200A
10
Firing type
Choose a correct firing type allows to optimize the thyristor unit for the installed load.
The firing type has already configured in line with customer requirements Zero Crossing for SSR input and
Burst Firing for Analog Input.
Caution: this procedure must be performed only by qualified persons.
10 1 Zero Crossing (ZC) with SSR input
ZC firing mode is used with Logic Output from temperature controllers and the Thyristor operates like a
contactor.
The Cycle time is performed by temperature controller. ZC minimizes interferences because the Thyristor unit
switches ON-OFF at zero voltage.
10 2 Burst Firing (BF) with Analog Input
The Burst Firing is similar to the Single Cycle, but consecutive cycles ON are selectable between 2-4-8 or 16,
with input signal equal at 50%. When is specified 2 the firing type have very fast cycle time, this selection is
suggested with diesel generator application.
Burst Firing is a method zero crossing that it reduces the electromagnetic interferences because the thyristor
switches at zero voltage crossing.
The example show the Burst Firing with Burst cycles: 4.
ON OFF
Voltage Supply (V)
Load Voltage (V)
SSR from controller
ON OFF
Voltage Supply (V)
Load Voltage (V)
26
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