LINK Systems OmniLink II Press Automation Control - Manual (Page 59)

August 30, 2002 Manual Version 1.0 4.10
Method 1. Slide at Top of Stroke
1. Inch the press to position the crankshaft within +/- 1 degrees of top dead center (0
0 -- slide at top of
stroke). This is important because the system uses the crank angle as its absolute reference and will
assume that the crankshaft position is at zero degrees when it calculates the Encoder Offset. If the
crankshaft is actually 5
0 from top dead center when you press the SET ZERO softkey or manually
enter an offset, as described in the following steps, you will incorporate a 5 0 error into the crankshaft
angle indication of the OmniLink II Operator Terminal. Make sure the Encoder Offset setting
shown on the screen is 0. If other than zero, select Encoder Offset and manually enter a setting of
zero before going to the next step by pressing the 0 number key and then the ENT(ER) key.
2. When you have positioned the crankshaft as closely as possible to top dead center, read the angle
display on the OmniLink II Operator Terminal. The number displayed must between 351 0 and 10 0 .
This is because a maximum misalignment of resolver to crankshaft of +/-10 0 can be corrected by the
Encoder Offset function. If the displayed angle is more than 10 0 from 0, you must manually de-
couple the resolver/encoder from the crankshaft and re-couple it within the required 351 0 to 10 0 .
3. When steps 1 and 2 are complete, use the arrow keys to select the Encoder Offset item on the menu
and press the SET ZERO softkey. The offset angle value will be automatically entered into the
Encoder Offset setting . This is the number that must be added to the actual resolver reading to get
0. If the resolver/crank misalignment angle was within the allowable limit of 351
0 to 10 0 when SET
ZERO was pressed, the angular display value will indicate 0 Ε.
Alternatively, you may enter the encoder offset manually using the number keys on the operator
terminal keyboard. To do this, refer to Figure 4.8.
a. b.
Figure 4.8 Determining Encoder Offset
Figure 4.8 illustrates how to manually determine encoder offset. If the crankshaft is positioned at
TDC (0
0
) and the angular position indicated by the angle display at the upper left corner of the
operator terminal screen reads 354 0 , as in Figure 4.8a, you need to add an encoder offset of 6 0 to
354 0 to get 360 0 . For a circle 0 0 and 360 0 are the same point, but the angle display will always
display 0 0 rather than 360 0 . If you manually use the number keys to set 6 0 as the offset and press the
enter (ENT) key, the angle display will then change to agree with the actual crankshaft angle of 0 0 .
If the crankshaft is positioned at TDC (0 0 ) and the angular position indicated by the angle display at
the upper left corner of the operator terminal screen reads 5 0 , as in Figure 4.8b, you need to add 355 0
to the 5 0 to be at 0 0 (360 0 ). The operator terminal does not make provision for negative offsets.
0 o & 360 o 0 o & 360 o
354
o
5
o