JUMO 709040 TYA-110 thyristor power unit Operating Manual - Manual (Page 50)

6 Settings
50 Power units 02.06
6.10 Firing-pulse inhibit
Inhibiting the firing pulses is a simple way of switching high powers. In phase-
angle control, the thyristor power unit commences with a soft start after firing-
pulse inhibit has been used. In burst-firing operation with a transformer load,
the power unit first starts up in phase-angle control and then switches over to
burst-firing.
A contact can be wired between Terminals 6 and 7 to shut off the thyristors at
the next zero-crossing point. This external contact can be a make contact or a
break contact, depending on the position of S21.
v Section 6.2 “Adjustment switches S1 — 21 and pin headers X503 / X504”
V In order to be able to disconnect a system, a contactor or main
switch must be fitted in the supply line circuit!
H
Only a make contact can be used as the external contact for a
master-slave economy circuit.
External
contact Internal switch
S21 Response
make (a) 1 Load is continuously shut off while the
external contact is closed.
break (b) 2 Load is continuously shut off while the
external contact is open.