4-11.High Frequency Controls; 4-12.Preflow Time Control (Optional) - Miller Electric SYNCROWAVE 250 Technical Manual

4-11. High Frequency Controls
4-12. Preflow Time Control (Optional)
Syncrowave 250
1
2
1
Y Place
High Frequency
switch in Off position before
using the shielded metal arc
welding (SMAW) process.
1 High Frequency Switch
START – (Up position) provides HF
for arc starting only. High frequency
turns on to help start arc when out-
put is enabled. High frequency
turns off when arc is started, and
turns on whenever arc is broken to
help restart arc.
Application:
HF Start is used when the DCEN
GTAW process is required.
OFF – provides no HF. Use OFF for
SMAW (stick electrode) welding.
CONTINUOUS – (Down position)
provides HF continuously through-
out the weld.
Application:
HF Continuous is used when the
AC GTAW process is required.
2 High Frequency Intensity
Control
Use control to change amount of
HF energy used to start and main-
tain the arc. Set as low as practical
to prevent interfering with electronic
equipment.
1 Preflow Time Control
Use control to set the length of time
(0–15 seconds) that gas flows be-
fore an arc is started.
Application:
Preflow is used to purge the imme-
diate weld area of atmosphere. Pre-
flow also aids in consistent arc
starting.
TM-353 Page 19