AW Gear Meters EMO-1005 - Manual (Page 22)

AW-Lake Company 8809 Industrial Drive, Franksville, WI 53126  web: www.awgearmeters.com
 Tel: 262-884-9800  Fax: 262-884-9810  Email: [email protected]
REV. 1a 05/98 EMO-1005 Manual.DOC
21
THE EMO-1005 PID OPERATIONS (Select 4)
When a 4 is selected in the previous screen, the channel card will be designated as a PI Controller with
the Transparent option.
The PI Controller with the Transparent option works the same as the standard PI - controller except that
the mode, when activated, takes the Analog Input and diverts it to the Analog Output. This feature
even overrides the HOLD signal. By doing this the EMO-1005 channel card becomes transparent.
This is used to override PID control mode during the flushing cycle. To do this the Limit 4 Output (pin
11) must be connected to +15V (pin 1) and the RESET (pin 9) must be connected to the Limit
Common (pin 15). This mode works well when testing the system components. As long as the Limit 4
is connected to +15V, the PI Controller will not start to regulate. (See Appendix J).
This is a very useful function for system evaluation and troubleshooting because PLC signal
commands can be routed directly through the unit to the other system components and the
response can still be evaluated via the EMO status display mode. For example the fluid regulator
limitations can be easily investigated in this manner.
The Transparent mode is used in applications where the rate (flow, rpm, speed, etc...) has to be
controlled and maintained. The PI-controller uses the frequency coming from the transmitter, as a
feedback signal, referred to as CURRENT RATE. The unit puts out an analog signal (4-20mA/0-5V)
to correct for the difference between SET VALUE and CURRENT RATE
SET-VALUE can be programmed via one of the following methods:
A.
4-20mA into Analog Input (Pin 5 & 6) (From PLC)
B. Programmed values (SET VALUE1/SET VALUE2) through the keyboard
entry. Programmed in Hz.
C. Set value can be entered through the RS-422 (RS-232) connection.
When using a channel as a PID controller it still works as a totalizer unit and rate indicator.
Some input pins and programmed values will have a different effect when the channel is used as
a PID controller.
(See Appendix J & Table Following)