AMETEK 1025 Foot & Palm Switches - Manual (Page 19)

15 Operating Manual
Chapter 3: Operating Instructions
NOTE: In some cases, stopping a continuous run press requires more than one
stroke of the ram. The standard Semelex II Safetimeter is incapable of
testing such an occurrence. To perform this type of test, the optional Remote
Tachometer is needed. Contact the factory for details.
3.11: Set Press Counterbalance
The Gemco Semelex II Safetimeter has the capability of checking both down and up
stop times to aid in setting the press’s counterbalance. For best results, the down
stop time test should be initiated at 90 degrees and the up stop time test at 270
degrees. It is important to stop the ram before engagement of the dies on the down
stroke, and before top dead center on the up stroke. However, on some presses,
the ram may take longer than 90 degrees to come to a complete stop. Test this
condition as follows:
1. On the downward stop time test, increase the Control Start Point (CSP) setting
to initiate a stop between 0 and 90 degrees. Continue increasing the CSP and
testing the press until a down stop of the ram can be made before the dies
have fully engaged.
2. On the upward stop time test, decrease the CSP setting to initiate a stop
between 180 degrees and 270 degrees. Continue decreasing the CSP and
testing the press until an upward stop of the ram can be made before the
top stop.
NOTE: It is important to test both the down and up stop times using the
same press control. Typically, an inch button or two-hand control
in the inch mode will be used since an up stop time test is
not possible in the single stroke mode using a two-hand control.
Adjust the counterbalance to obtain equal down and up stop times. This sets
the counterbalance at the optimum point.
Always follow the press manufacturer’s recommendations when setting the
counterbalance. Several safety distance and/or stop time tests must be
performed after the setting of the counterbalance to ensure safe press
operation and guarding.
8. When the ram is on the up stroke, press the power switch ON. When the
ram goes through the top of the stroke and crosses the 90 degree point, Auto-
Hand will release and press the E-STOP button or interrupt the presence
sensing fi eld with Auto-Flag.
9. After the press stops, verify that the ram has not gone through the bottom
of the stroke or that the dies have engaged. If either of these conditions
have occurred, the reading is inaccurate. Increase the CSP setting slightly and
test until neither of these conditions occur.