Amada Miyachi Unitek STA-100A, Operation Manual, Page: 57 / 154

CHAPTER 4: OPERATING INSTRUCTIONS
STA SERIES AC CONTROLS
990-351 4-9
Cascading (Requires Multiple SCRs)
1 To change the information in the schedule screen the control must be in
PROGRAM
. From the
schedule screen press the
PROGRAM/SAVE
button so that the red
READY
indicator is OFF and
the green
PROGRAM
indicator is ON.
2 From the
MODE
screen, highlight the
SYSTEM VALUES 1
screen, then press the
DATA +/-
key.
3 Press to select the
MAX # OF SCR=
field. Use the
+
key to input the number of SCRs in the
control.
4 Use to select the
VALVES STATUS
field. Press the + key to display the
System Valve
Status
screen. Use to select the
SCR
field for the first valve. Use the + or – key to select
which SCR should be tied to this electrode valve. Use to select the SCR field for each of the
remaining electrode valves. Use the
+ or – keys to select the SCR that is associated with each
electrode valve. You may also select
N/A
.
5 To select the schedule you desire, return back to the main schedule screen by pressing the
Schedule
button then select the schedule number using the
+
or
–
(
ON
or
OFF
) keys.
6 To change the weld schedule data, press to scroll through and enter the time (in cycles)
desired for
SQD, SQZ, UP1, W1, DN1, CO, UP2, W2, DN2, HO
and
OFF
. In each field, use the + or
– keys to change the time desired. See Appendix D, System Timing for a graphical
representation of each of these periods.
7 Press again and enter the weld current or percent heat desired for
W1
. See the description of
the
SYSTEM VALUES SCREEN 1
for more information on the %heat and constant current weld
modes.
8 Press and enter the weld current or percent heat desired for
W2
.
9 Press to move to the
ElectroValve
and
SCR
selection. Use the + or – keys to select the
desired electrode valve and SCR.
10 To select the valve
ON/OFF
position, press the
VALVES
button located below the main screen,
to go to the valve screen.
11 Press to toggle through the available valves. Use the + or – keys to turn each valve on or off
in that schedule.
12 Use the
MONITOR
screen to set welding limits (see Chapter 3, Using STA Series Control
Functions, Section IV ).
13 Press the
MODES
button to display the modes screen. Push twice to select the
WELD MODE
field. Press the
DATA +/-
key as required to select the
SUCCESSIVE
or
CHAINING
weld mode.
Use
SUCCESSIVE
when the intention is to stop welding between each schedule, remove, and
reactivate the
Start
signal to resume welding with the next schedule in the sequence. Use
CHAINING
when the intention is to fire all the linked schedules in sequence with one input of
the Start signal.