Machine Data and Cam Data
8-29
FM 452 Electronic Cam Controller
C79000-G7076-C452-04
Address
(relative)
Name
Type
Initial Value
Comment
+ 10.0
LTIME
INT
0
Lead Time
Range:
(0 to 53686)
100
s with a maximum of 16 cams
(0 to 65535)
100
s with a maximum of 32, 64 or 128 cams
Delays in the connected switching elements can be compensated by specifying a lead time. You enter
the lead time in steps of 100
s. You can assign a lead time for each cam. The lead time applies to the
cam start and cam end.
Lead Distance
The lead distance of a cam is recalculated depending on the current feedrate and the lead time. The
entire cam is shifted in the direction of the actual value by this distance. The range set is known as the
“static range” and the range calculated based on the lead time is known as the “dynamic range”.
Lead distance = lead time
current feedrate.
Calculation of the lead distance of all cams is made within 1/4 of the longest set lead time on the
FM 452. If you set a very high lead time for a cam, the dynamic adjustment is calculated less often.
Actual Lead Time
You can calculate the actual lead time as follows:
Calculate the cam cycle time: This is the time in which the FM 452 has completely processed all
cams and depends on the number of cams in use (see table Page 8-23).
Calculate the actual lead time with the following formula:
Where:
Lead time
act
is the lead time set by the FM 452
Lead time
I
is the lead time you specified.
Integer () means that in the calculation inside the brackets, only the value before the decimal point is
taken into account.
The maximum error of the lead time
act
is always less than the cam cycle time
4.
Example:
The following values are specified:
Number of cams: maximum of 32 cams
cam cycle time: 40.96
µ
s
lead time
L
= 1000
µ
s
Result: You obtain an actual lead time of 983
µ
s.
A lead time in conjunction with an absolute encoder (SSI) and inverted count direction is not
permitted.
Lead time
act
= integer
(
Cam cycle time
4
Lead time
I
Cam cycle time
4
)
Note
The actual lead time is always less than the set lead time. It can be 0 even though
the set lead time is
100
s.
The lead distance on a rotary axis must be less than the rotary axis range and the
non-active part of the cam. This must be guaranteed for all speeds.
Содержание SIMATIC FM 452
Страница 8: ...Contents viii FM 452 Electronic Cam Controller C79000 G7076 C452 04 ...
Страница 14: ...Product Overview 1 6 FM 452 Electronic Cam Controller C79000 G7076 C452 04 ...
Страница 28: ...Installing and Removing the FM 452 3 2 FM 452 Electronic Cam Controller C79000 G7076 C452 04 ...
Страница 36: ...Wiring the FM 452 Electronic Cam Controller 4 8 FM 452 Electronic Cam Controller C79000 G7076 C452 04 ...
Страница 38: ...Installing the Software 5 2 FM 452 Electronic Cam Controller C79000 G7076 C452 04 ...
Страница 62: ...Programming the FM 452 6 24 FM 452 Electronic Cam Controller C79000 G7076 C452 04 ...
Страница 68: ...Putting the FM 452 into Operation 7 6 FM 452 Electronic Cam Controller C79000 G7076 C452 04 ...
Страница 130: ...Settings 9 32 FM 452 Electronic Cam Controller C79000 G7076 C452 04 ...
Страница 140: ...Encoders 10 10 FM 452 Electronic Cam Controller C79000 G7076 C452 04 ...
Страница 146: ...Diagnostics 11 6 FM 452 Electronic Cam Controller C79000 G7076 C452 04 ...
Страница 162: ...Samples 12 16 FM 452 Electronic Cam Controller C79000 G7076 C452 04 ...
Страница 168: ...Technical Specifications A 6 FM 452 Electronic Cam Controller C79000 G7076 C452 04 ...
Страница 174: ...Connection Diagrams B 6 FM 452 Electronic Cam Controller C79000 G7076 C452 04 ...
Страница 200: ...Data Blocks Error Lists C 26 FM 452 Electronic Cam Controller C79000 G7076 C452 04 ...