Siemens SIMATIC 505 - Definitions of Constants; Constant 1; Constant 2

Software Interface
2-13
2.6.1
The constants (V -memory locations 1–14 of each of the five profiles) are
defined in the following paragraphs.
2.6.2
Constant 1 contains the module sample rate for this profile: 0–32767 in
PLC = 0–32.767 ms. The normal value is 5000 or 5 ms; the minimum value
is 1500 or 1.5 ms.
2.6.3
For all profiles except pack and hold, constant 2 contains the maximum
profile time to transition: 0–32766 in PLC = 0–327660 ms or 327.66 seconds.
For example, 325 = 3250 ms or 3.25 seconds. Note that 32767 = infinite
time.
For pack and hold profile, constant 2 contains the minimum position of the
injection ram to transition (end): 0–32000 in PLC = 0–10 V input. For
example, 16000 = 5 V or 50 percent of scale.
2.6.4
For clamp close profile, constant 3 contains the lock-over velocity value (one
of three lock-over variables stored in constants 3, 4, 5). The lock-over
velocity provides a clamp lock-over feature for toggle machines by producing
an additional burst of hydraulic flow and/or pressure for a specific amount
of time at the end of the clamp close profile to force the toggle mechanism
over center .
If the lock-over time (constant 5) is not zero, the lock-over velocity feature
will be activated, providing hydraulic flow and pressure for a specified time
after completion of the clamp close profile, whether by position: 0–32000 in
PLC = 0–10 V output. For example, 8000 = 2.5 V or 25 percent of scale.
For injection and pack and hold profiles, constant 3 contains the maximum
pressure value required to transfer from this profile. T o disable constant 3,
load 32767 or you can inhibit pressure transfer at different steps by using
constant 10 Bits 14 –16. For plasticate profile, constant 3 contains the cure
timer value.
Y ou can specify a pressure threshhold before you enter a clamp open profile.
Download table 179 (clamp open constant 3) specifies a value for comparison
to channel 4. If a current channel 4 value is equal to or less than the value
at download table 179, a clamp open profile is started.
Definitions of
Constants 1–14
Constant 1
Constant 2
Constant 3