Eaton ELC-PB - Page 82

2. Programming Concepts
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X21 drives M1241 to decide C241 is addition or subtraction.
When X20=ON and RST instruction is executed, clear C241 to 0 and reset output contact to off.
When X22=ON, C241 receives count signal from X0 and counter will count up (+1) or count down
(-1).
When counter C241 attains settings K5, C241 will be ON. If there is still signal input for X0, it will
keep on counting.
C241 in ELC-PB, ELCB-PB and ELC-PC/PA/PH controllers has external input signals to reset X1.
C241 in ELC-PV controllers has external input signals to reset X2 and start X3.
The external input contact of reset signal of C241 (HHSC0) in ELC-PV controllers is disabled by
M1264. The external input contact of start signal is disabled by M1265.
The internal input contact of reset signal of C241 (HHSC0) in ELC-PV controllers is disabled by
M1272. The internal input contact of start signal is disabled by M1273.
The counting modes (normal frequency or double frequency) of C246 (HHSC0) in ELC-PV
controllers can be set up by D1225. The default setting is double frequency mode.
X22
X0
0
1
2
3
4
5
X20
X21,M1241 contact
6
7
6
5
4
3
counting up
counting down
C241
present
value
Y0, C241 contact
1-phase 2 inputs high-speed counters:
Example:
LD X20
RST C247
LD X21
DCNT C247 K5
LD C247
OUT Y0
C247
Y0
X21
C247 K5DCNT
C247RST
X20
When X20=ON and RST instruction is executed, clear C247 to 0 and reset output contact to off.