Rockwell Automation 1771-CFM,D17716.5.99 CONFIGURABLE FLOWMET - Manual (Page 44)

4–10 Configure the CFM Module
Publication 1771Ć6.5.99 - December 1995
Storing Count Value
In the Totalizer and Nonresettable Totalizer modes, the CFM module
stores the current count based on these values:
Value BTW word # Use to
Prover Run Initialize 1 (bits 08Ć11)
initialize an input channel for prover inputs on the gate or to store current
count value (if prover not used).
If OFF (=0) Ċ CFM module stores the current count every time there is a
low to high transition at the appropriate gate input terminal. As each value
is stored, the Prover Status (BTR words 4 & 5, bits 4Ć6) will be updated to
indicate a new value. Prover Status toggles between 6 and 7 (hex) as
each new gate transition occurs:
6 = prover not active & new store count A
7 = prover not active & new store count B
If ON (= 1) Ċ the CFM module resets to 0 any previously stored count
contained in Store Count Value
(BTR words 13 & 14, 22 & 23, 31 & 32, or 40 & 41) and then waits for the
proper number of gate transitions to occur
(2 for unidirectional and 4 for bidirectional).
As the gate transitions occur, Prover Status (BTR words 4 & 5, bits 4Ć6) is
updated accordingly, dependent upon the current state of the prover:
0 = prover not selected
1 = prover running, but not active
2 = prover running Ć past the 1st switch in forward leg
3 = prover is done with forward leg, returning at this time
Ć midĆrun value (bidirectional only)
4 = prover is returning on 2nd leg (bidirectional only)
5 = prover is done with run (BTR word 13/14 contains prover count value)
The prover run is aborted and the Prover Status is set to 0 any time
Prover Run Initialize is set to 0. The time between gate transitions must be
long enough to allow the PLC processor to perform a BTR and get the
updated stored value.
Debounce Filtering 5, 15, 25, 35 (bit 10)
debounce gate input for a period of 1s.
If ON: CFM module takes appropriate action at the first low to high
transition (at the gate input) and ignores all other gate transitions for 1s.
If OFF: CFM module takes appropriate action at every low to high
transition (at the gate input).