5ć12, 3 downćcounter instruction – Rockwell Automation 1772-LP3 PLC - 2/30 Programmable Controller Programming and Operations Manual User Manual
Page 110

Timer and Counter Instructions
Chapter 5
5Ć12
The Down-Counter (CTD) instruction subtracts one from its Accumulated
Value for each false-to-true transition of its rung conditions (Figure 5.9).
Because only the false-to-true transition causes a count to be made, rung
conditions must go from true to false and back to true before the next count
is registered.
Figure 5.9
DownĆCounter Instruction
|ą|
02
( CTD )
113 054
PR 100
AC 150
The CTD accumulated value is retained when:
Mode Select Switch is changed to the PROGRAM position
Rung conditions go false
Power outage occurs provided memory backup power is maintained for
CMOS RAM memory
Each time the CTD rung goes true, bit 16, the enabled bit, is set on. When
the Accumulated Value is greater than or equal to the Preset Value, bit 15 is
set on. When the Accumulated Value goes below 000, bit 14 is set on to
indicate an underflow condition and the CTD continues down-counting
from 999.
Normally, the Down-Counter instruction is paired with the Up-Counter
instruction to form an Up/Down Counter, using the same word address,
AC value and PR value (Figure 5.10).
5.2.3
DownĆCounter Instruction
- 20P PowerFlex DC Drive - Frame D Bimetal Thermostat (10 pages)
- 1336S_F_T_E_R F Frame Snubber Resistor Repl. (6 pages)
- 22-COMM PowerFlex 4-Class DSI (Drive Serial Interface) Network Communication Adapter (4 pages)
- 8-545 Plug In Solid State Relay (2 pages)
- 20-HIM-B1 PowerFlex 7-Class HIM Bezel (DPI) (4 pages)
- 100 Contactors with DC Coil (2 pages)
- 100 Contactors with DC Coil (1 page)
- 20P PowerFlex DC Drive - Frame D Switching Power Supply Circuit Board (6 pages)
- 140G-MTFx_MTHx_MTIx_MTKx Trip Unit Installation-140G-M (6 pages)
- 45BRD Analog Laser Sensor (4 pages)
- 20D Multi-Device Interface Option Board for PowerFlex 700S Drives (20 pages)
- 56RF RFID 18 mm Cylindrical Transceiver (2 pages)
- 42KC Miniature Rectangular: 5V DC Version (2 pages)
- 20P PowerFlex DC Drive - Frame A Switching Power Supply Circuit Board (16 pages)
- 21P-MISC-A-TP-2 Transition Tube Kit #C19-6/7 For PowerFlex 755 w/OEM Liquid Cooling Fr 6/7 Drive (2 pages)
- 42BT Background Suppression Sensor (3 pages)
- 42CB High Speed 18mm Cylindrical (4 pages)
- 140EX-JE2_JE3 Molded Case Circuit Breaker (4 pages)
- 140G-K-EAM1A Early Make Aux Contact for Rotary Handle Oper Mech-140G-K (1 page)
- 140G-K-EAM1A Early Make Aux Contact for Rotary Handle Oper Mech-140G-K (3 pages)
- 20-HIM-A6 PowerFlex (Human Interface Module) (74 pages)
- 42CF General Purpose 12mm Cylindrical (4 pages)
- 20D PowerFlex 700S Phase II Drive Frames 1...6 (80 pages)
- 140EX-HE1_HE2 Molded Case Circuit Breaker (6 pages)
- 140EX-HE1_HE2 Molded Case Circuit Breaker (4 pages)
- 20B PowerFlex 700 Custom Firmware - Pump Off (12 pages)
- 20-WIM-N4S DPI Wireless Interface Module (92 pages)
- 140U H-Frame Circuit Breaker Fixed and Adjustable Thermal Trip (2 pages)
- 140U H-Frame Circuit Breaker Fixed and Adjustable Thermal Trip (7 pages)
- 60-2619, 42JS Swivel/Tilt Mounting Bracket (1 page)
- 22A PowerFlex 4/40/400 Flange Mount (4 pages)
- 45MLA Controller Installation Instructions (16 pages)
- 20P PowerFlex DC Drive - Cooling Fan for Frame A Drives Above 73A at 230V 460V AC (6 pages)
- 42JS Series 7000 to 42JS VisiSight Replacement Kit (2 pages)
- 22A PowerFlex 4-Class HIM Bezel (DSI) (4 pages)
- 42CS Stainless Steel Photoelectric Sensors (4 pages)
- 20L-LL PowerFlex 700L Liquid-to-Liquid Heat Exchanger (40 pages)
- 20P PowerFlex DC Drive - Frame B SCR Modules (20 pages)
- 22B PowerFlex 40 Quick Start FRN 5.xx - 6.xx (161 pages)
- 22B PowerFlex 40 Quick Start FRN 5.xx - 6.xx (22 pages)
- 22F PowerFlex 4M Input RFI Filters (2 pages)
- 45LFM Capacitive Label Sensor (4 pages)
- 140G-Rx Installation Instruction-140G-R (29 pages)
- 140G-Rx Installation Instruction-140G-R (2 pages)
- 22C PowerFlex 400 AC Drive Quick Start - FRN 1-4.xx (28 pages)