FX Series Programmable Controllers Devices in Detail 4
4-29
4.11.5 1 Phase Counters - User Start and Reset (C235 - C240)
These counters onl
use one input each.
When direction fla
M8235 is ON, counter
C235 counts down. When it is OFF, C235
counts up.
When X11 is ON, C235 resets to 0 (zero). All
contacts of the counter C235 are also reset.
When X12 is ON, C235 is selected. From the
previous counter tables, the correspondin
counted input for C235 is X0. C235 therefore
counts the number of times X0 switches from
OFF to ON.
Device specification:
• All of these counters are 32bit up/down rin
counters. Their countin
and contact
operations are the same as normal 32bit up/down counters described on pa
e 4-21.
When the counters current value reaches its maximum or settin
value, the counters
associated contacts are set and held when the counter is countin
upwards.
However, when the counter is countin
downwards the contacts are reset.
Setting range:
• -2,147,483,648 to +2,147,483,647
Direction setting:
• The countin
direction for 1 phase counters is dependent on their correspondin
fla
M8 ; where is the number of the correspondin
counter, (C235 to C240).
When M8 is ON the counter counts down,
When M8 is OFF the counter counts up.
Using the SPD instruction:
• Care should be taken when usin
the SPD applied instruction (FNC 56). This instruction
has both hi
h speed counter and interrupt characteristics, therefore input devices X0
throu
h X5 ma
be used as the source device for the SPD instruction. In common with
all hi
h speed processes the selected source device of the SPD instruction must not
coincide with an
other hi
h speed function which is operatin
, i.e. hi
h speed counters
or interrupts usin
the same input.
When the SPD instruction is used it is considered b
the s
stem to be a 1 phase hi
h
speed counter. This should be taken into account when summin
the maximum com-
bined input si
nal frequencies - see the previous section.
X12
K1234
C235RST
X10
X11
M8235
C235
