Lincoln Electric NA-5N Service Manual page 116

F-63
WIRE SPEED ACCURACY TEST
3. Check for the proper drive roll revo-
lutions per minute. (RPM)
A. Adjust the STRIKE speed con-
SPEEDMETER
CALIBRATION
PIN
21*
57F**
57**
95
95S***
142
142T***
* Present on HI -Speed NA-5 speedmeter board only. ** Early speedmeter pins were labeled 55F and 55,
*** Early speedmeter PC boards did not include these calibration pins.
TROUBLESHOOTING & REPAIR
trol to obtain the SET speed
specified for the speedmeter
calibration pin and head ratio
specified per Table F.5 While
pressing the INCH down button
count the drive roll revolutions in
60 seconds. The drive roll revo-
lutions and actual speed reading
should match Table F.5
TABLE F.5
HEAD SET SPEEDMETER
RATIO READING (IPM)
READING (IPM)
21/1 0.27 (IPM X 1000)
57/1
57/1
95/1
95/1
142/1
142/1
(Continued)
B. If the readings do not match the
number in Table F.5 refer to the
Meter Circuit Accuracy Test .
DRIVE ROLL
RPM
50 +/- 2
268 50 +/- 1
262 50 +/- 1
249 50 +/- 1
265 50 +/- 1
250 50 +/- 1
260 50 +/- 1
respectively.
NA-5
F-63
ACTUAL
SPEEDMETER
0.27 +/- 0.01
(IPM X 1000)
268 +/- 2
262 +/- 2
249 +/- 2
265 +/- 2
250 +/- 2
260 +/- 2