Minster IOI, Service Manual

Page: 21 / 92

DIGITAL SPEED METER CALIBRATION
The switches and potentiometer used for calibration of
the Digital Speed Meter are accessible through a cutout
in the rear cover plate of the unit. If the installation does
not permit access to these controls, temporarily
remove the meter mounting screws and position the
unit so that the controls can be adjusted.
WARNING
WHEN PERFORMING CALIBRATION ADJUST-
MENTS, POWER IS PRESENT IN THE PRESS CON-
TROL AND THE METER TERMINAL STRIP. USE
EXTREME CAUTION WHEN CALIBRATING THIS
UNIT TO PREVENT ACCIDENTAL ELECTRICAL
SHOCK.
Equipment Required:
•
Tachometer or other equipment to accurately deter-
mine press speed.
•
Small flat blade screwdriver.
To Calibrate The Digital Speed Meter:
1. Set the 0-200/0-2000 Switch to the correct range
position. (See Figure 5C for switch location.) If max-
imum speed of the press is 200 S.P.M. or less, place
the switch in the 0-200 position. If the maximum
press speed exceeds 200 S.P.M., place the switch
in the 0-2000 position. (This moves placement of
readouts decimal point.)
NOTE: With the switch in the 0-200 position, the
digit on the extreme right side of the display
is not used and will remain blank. In this
position, the reading is obtained from the
first three digits. In the 0-2000 position, the
digit on the right is a fixed “0”, which will
require speed changed in increments of 10
S.P.M. before the display is changed.
2. The High/Low Range Switch extends the range or
gain of the fine-adjustment potentiometer and
should be used as necessary to achieve correct
readout of the press speed. (See Figure 5C.)
3. With the slide cycling continuously at full speed,
check the actual number of strokes per minute using
an accurate tachometer or other dependable means.
4. Now adjust the potentiometer and the High/Low
Range Switch so that the meter will display the cor-
rect press speed in strokes per minute.
SERVICING PROCEDURE:
In the event a problem is encountered with the Bul. 490-
0246 Digital Speed Meter, perform the following tests:
1. Check for the presence of 100 volts A.C. between
the “A.C.” meter terminals. (Voltage must be pre-
sent.)
2. Check for the presence of tachometer generator
voltage between meter terminals marked “INPUT”
(+) and (-). (Voltage should range between 30 to 60
volts A.C. with the slide cycling at full speed — or
drive motor output shaft turning at full speed.)
C - 8
Figure 5C. Rear view of Digital Speed Meter.
SERIAL NO.
R-8703-019
High Range Low Range
Fine Adjustment
Potentiometer
0 - 200 S.P.M. 0 - 2000 S.P.M.
Terminal Strip
INPUT
AC AC
MUST BE ADJUSTED WHEN INSTALLED
!