Model 227 operation manual – Arc Machines 227 User Manual
Page 74

MODEL 227
OPERATION MANUAL
Doc # 740063 Rev E
SECTION VII - CALIBRATION
7.2
CURRENT CALIBRATION (continued)
13. Wait for machine to advance to and even level or 10 Amps.
14. During Weld Seq. Even Levels the DMM should read as follows:
Center Plate Test Points = 0.20 VDC +/- 0.001 VDC.
(0.199 VDC to 0.201 VDC)
AMI External Shunt = 10 mv DC +/- 0.025 mv DC
( 9.97 mv to 10.02 mv )
If out of tolerance adjust the “Current Off Adj.” Current offset trimming
potentiometer adjusting screw on the Center Plate.
15. Repeat steps 13 and 14 until no adjustments are required.
16. Press the SEQ STOP key.
17. After Postpurge turn the power off, remove all test leads. If calibration is
complete lower the computer cover and install the retaining screws
7.3
ARC VOLTAGE CONTROLLER (AVC) CALIBRATION
A weld schedule is required for AVC calibration. The first time calibration is
performed this schedule will have to be CREATED. Step 1 (next page) has a place
for writing in the Weld # after it has been created.
NOTE
The adjustment for AVC Calibration is located on the Center Plate under the
computer cover (front panel housing). Turn the Power OFF and unscrew the two
computer cover retaining screws in the front. Lift up on the cover and expose the
center plate. Prop the cover up so it will not fall but make sure you can still operate
the system. Locate the adjustment screw labeled “TR3” and turn the power back ON..
1. Select Weld Schedule Number ____ and verify that the FIRST PASS
it is programmed as follows:
LVL
1
TIME
20
PRI-AMP--BCK
100 100
PRI-PULSE-BCK
0.00 0.00
LVL
1
PULSE
OFF
ROT
OFF
PRI--IPM-BCK
0.00 0.00
LVL
1
PRI-WF-BCK
000 000
PRI-AVC-BCK
10.0 10.0
AVC MODE
CONT
7.4