Rockwell Automation 1746-MPM INSTALL INSTRUC MOLD PRESSURE - Manual (Page 6)

6 Mold Pressure Module
Publication 1746-5.13 July 1998
Commands and status via the I/O image table
The module uses I/O image word 0 for bit-level commands from the SLC
processor and returns bit-level status to the SLC processor. You will use
these command and status bits in your ladder logic.
Addresses: Commands = O:e.0/xx, Status = I:e.0/xx (e = slot #)
(
Scaled data transferred from the module
The SLC processor reads mold pressure as counts (0-4095) from the
module’s A/D converter. Your ladder logic must convert counts to PSI.
Important: For the computation rung, see section 10, ladder example 5.
For low-level sensor signals (module gain = 450)
This equation can be re-arranged to:
For high-level sensor signals (module gain = 1)
Bit commands to the module Bit status from the module
00 trigger 1, start machine cycle 00 channel 1 alarm
01 trigger 2, injection fill time 01 channel 2 alarm
02 trigger 3, screw backup time 02 cycle time alarm
03 trigger 4, mold closed time 03 channel 1 loss of sensor
04 set channel 1 zero offset 04 channel 2 loss of sensor
05 set channel 2 zero offset 05-07 spare
06 shunt calibration bit - Never set
concurrently with bit 04 or 05 08 trigger 1 is ON
09 reading chnl 1 zero offset
07-15 reserved 10 reading chnl 2 zero offset
11 reading redundant permissive
12-15 reserved
PSI
Counts
π D
2
----

 2

 9vdc
L
------------ ×
x
4095xCounts
10vdc
----------------------------------
-------------------------------------------------------------------------- = Where:
D = diameter of the ejector pin
L = full-load rating of the sensor
PSI
Counts L ×
D
2
2894.58
×
-------------------------------- =
PSI
Counts
π D
2
----

 2

 10vdc
L
--------------- ×
x
4095xCounts
10vdc
----------------------------------
----------------------------------------------------------------------------- =
PSI
Counts L
×
D
2
3612.2 ×
-----------------------------
=
Important:
For a sensor with 20mA full-load output,
use this same computation.