Danaher Motion B8961, Operator'S Manual

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B8961 and B8962 User Manual
52
Non-Volatile Variables
The non-volatile variables (EE1)-(EE20) are twenty user accessible variables that
retain their values through po wer cycles, warm boots,and system resets.Standard
user variables are reset at power down or reset.Each time one of these variables is
changed (i.e.used on the left side of an equal (=) sign,the new value is written to
and stored in the user non-volatile EEPROM.
CAUTION
Caution must be observed when using these variables. Since EE
have a limited read/write lifetime (100,000 writes before failure),
variable values that change frequently should not be stored as EE
system variables. Examples include loop-count variables, and
POS1 and POS 2 variables. The SmartDrive will allow only 1,000
EE writes between power cycles. This limit has been set to pre-
vent a simple programming mistake or misunderstanding from
permanently damaging the SmartDrive’s non-volatile memory.
When this write limit has been exceeded, all programs will stop
running, an error message will be displayed, and the appropriate
status bits will be set.
The EE system variables were originally developed for use in batch manufacturing
applications where a number of variable setup parameters must be entered at the
start of each part run.These same setup parameters can then be used through any
number of power cycles,or machine resets.
Example:A program called [Set-up] is run at the start of each part run to initialize a
number of variable part parameters.During production the program called [PARTS]
is run.This program
reads from the EE variables,but does not generate any writes
to the EE,so the lifetime of the EE is not compromised.
[Set-up]
MS1,”Feed length?:”
Writes string beginning at character 1,top line
IV12,(LENGTH),1,15 Loads the part length into volatile user variable
(LENGTH)
MS1,”Feed Speed?:” Writes string beginning at character 1,top line
IV12,(SPEED),.05, 5 Loads the speed into volatile user variable (SPEED)
(EE1)=(LENGTH) Loads the length into non-volatile system variable (EE1)
(EE2)=(SPEED) Loads the speed into non-volatile system variable (EE2)
EN
[PARTS]
[PARTS] runs on power up,unless new parameters
are entered.
(LENGTH)=(EE1) Load the part specific variable from the non-volatile
variables.
(SPEED)=(EE2)
LP(NUMBER)
Loop (NUMBER) of times
DI(LENGTH) Move (LENGTH)
VE(SPEED) at (SPEED) velocity
GO
OT1 TD.1 OT0
Toggle output to indicate part done
EB End the loop Block