Eaton ELC-PB, Programming Manual

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3 . I n s t r u c t i o n S e t
M N050 03003E F or mo re infor ma tio n vi sit:
w w w. e a t o n . c o m
3-121
Points to note:
1. The output contact of a high-speed counter and the compare outputs of the DHSCS
instruction, the DHSCR instruction and the DHSZ instruction will all operate normally when
there are counted inputs. If instructions such as, DADD, DMOV…etc. are used to change the
present value of a high-speed counter to equal the preset or compare value, the output will
not energize because there are no counted inputs.
2. High-speed counters for ELC-PB, ELCB-PB series models:
ELC-PB, ELCB-PB models: total counting frequency (X0~X3) is 20 KHz.
1-phase 1 input 1-phase 2 inputs 2-phase 2 inputs Type
Input
C235 C236 C237 C238 C241 C242 C244 C246 C247 C249 C251 C252 C254
X0 U/D U/D U/D U U U A A A
X1 U/D R R D D D B B B
X2 U/D U/D
R R R R
X3 U/D R S S S
U: Increasing input A: A phase input S: Start input
D: Decreasing input B: B phase input R: Reset input
Input points X0 and X1 can be used as high speed counter inputs for 1-phase 1 input up to
20KHz. Input point X2 and X3 can be used as high speed counter inputs for 1-phase 1 input
up to 10KHz. But total counting frequency of these input points should be less than or equal
to total frequency 20KHz. If the input is 2-phase 2 inputs signal, the frequency will be four
times the counting frequency. Therefore, the counting frequency of 2-phase 2 inputs is
4KHz.
In ELC-PB, ELCB-PB models, DHSCS and DHSCR instruction cannot be used more than 4
times.
3. High-speed counter provided in ELC-PC/PA/PH series models:
ELC-PC/PA models: total counting frequency is 30 KHz
1-phase 1 input 1-phase 2 inputs 2-phase 2 inputs
Type
Input
C235 C236 C237 C238 C239 C240 C241 C242 C244 C246 C247 C249 C251 C252 C253 C254
X0 U/D U/D U/D U U U A A B A
X1 U/D R R D D D B B A B
X2 U/D U/D R R R R
X3 U/D R S S S
X4 U/D
X5 U/D
U: Increasing input A: A phase input S: Start input
D: Decreasing input B: B phase input R: Reset input
Input points X0 and X1 can be high speed counter inputs for 1-phase 1 input up to 30KHz.
Input points X2 ~ X5 can be high speed counter inputs for 1-phase 1 input up to 10KHz. But
the total counting frequency of these input points should be less than or equal to the total
frequency 30KHz. If the input is 2-phase 2 inputs signal, the frequency will be four times the
counting frequency. Therefore, the counting frequency of 2-phase 2 inputs (C251, C252,
C254) is 4KHz and the counting frequency of 2-phase 2 inputs (C253) is 25KHz
.
In ELC-PC/PA series models, DHSCS, DHSCR and DHSZ instruction cannot be used more