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Encyclopedia of internal registers of the FX series PLC

When it performs scans on internal components x, y, m, c, s, t, counts the number of signals. When the count reached the set value for the counter, countercontact action, used in the control system of the corresponding function. Low counters can not only record from the input terminal (input relay) switching signals, and can record contacts for other components within the PLC signals.
Internal counter classified according to their recorded switching frequency, can be divided into low and high-speed counters.
1) low-speed counter
There are four categories:
16-bit general-purpose counter increases: C0 C99 (100 points); set value range K1 K32767
16-bit power outages keep increasing counter: C100 C199 (100 points), set the interval to K1 K32767
32-bit bidirectional counter general increase/decrease: C200 C219 (20 points), set value range K-2147483648 +214783648
32-bit power kept increasing/decreasing bidirectional counter: C220 C234 (15 points), set value range K-2147483648 +214783648
2) internal high speed counter (c)
High speed counter can only burn the agreed input terminal (input relay) into an external signal, and the signal frequency can be as high as thousands of kHz. Can also reset operation directly from the input terminals.
C235 C255 high speed counter number 21, fall/rise are 32-bit bidirectional counter, count increase or reduction of the count by the specified special auxiliary relays decided or determined by the specified input terminal, set the interval to K-2147483648 +214783648.
High speed counter normally four classes are named:
1 no start/reset terminals: C235 C240;
1phase bi-directional: C246 C250;
2phase A-Bphase: C251 C255;
High speed counter input terminal (input relay) agreed between the following table:
Note: U-add count input; dminus count input A-A input B-B input R-reset input; s-start input.
Running principle of high speed counter is interrupted, thus it is independent of the scan period of coils in a continuous mode of the selected counters to represent the continuous effective counter and its associated input, other high-speed processing can no longer use its input terminals.
(1) type 1 high speed counter C235 C240
No start/reset end

Set value range
Start/Reset end


N increase counter, when the count value reaches the set value, the contacts and keep count reduction, number values are reset.
N 1phase counter direction depending on their corresponding to flag M8C235 C245counter.
(2) 1phase bi-directional high speed counter C246 C250
1phase bidirectional counter has an input terminal used for counting, other input for count reduction. Additional is required from different input reduction arrangements rather than using special auxiliary relay contract. Certain counter with reset and start input.
(3) 2phase A-Bphase high speed counter: C251 C255
2 phase 2 input (C251 C255,1 or 2, battery backup) up to 2 phase 2 fall/rise 32-bit binary counter. It is interrupted count, has nothing to do with the scanning cycle. These counters also have some logical operation is independent of the implementation and output operations application instructions. Counters component is selected, start, reset and that corresponds to the input signal can be used. Phase a decision and b believe that the counter is count increase or a decrease in count.
For example: when a wave ON state:
Phase b input OFF ON: increased count
Phase b input ON OFF: reduction count

FX series PLC internal program components-auxiliary relay (m)

For PLC programming, the coil and contacts can only be used in a program, not direct external inputs and outputs, is often used as a staging and so on.
Auxiliary relays use decimal address number.
Auxiliary relay is divided into the following categories:
General auxiliary relays M0~M499 (500 points)
power outages keep auxiliary relays M500~M1023 (524)
Equipped with backup batteries, used to save state before the power outage, and reproduce the situation at run time.
Special auxiliary relays M8000~M8255 (256 points) the system provides for specific purposes, check the product manual when using.
Coil driven by the PLC itself, users can directly contact.
For example: M8000 (monitoring), M8002 (initial pulse), M8013 (1s clock pulse)
After the user drive coil, PLC for a specific action.
Example: M8033 PLC stops output remains, M8034 refers to the PLC prohibits all output, fixed 1s M8013 clock pulse

Main extensions of FX series PLC

The delay has a maximum value of FX series PLC, such as delay greater than the maximum value of the timer can be used more than one timer delay relay.
The specific method is:
(1) before using a normally open start the next timer timer.
(2) counter and timer work.

FX2N series PLC data register (d)

Registers of programmable controller used to store the analog control, position control, data I/O required for data and parameters. Every data register is 16-bit (MSB as the sign bit), you can use two data consolidation for 32-bit data registers (the highest bit is the sign bit).
(1) with data registers D0 D199 (200 points)
If no other data are written, it is write the data does not change. However, the PLC status by running (RUN) stop (STOP) when all of the data is cleared.
Special auxiliary relays M8033 set to 1, while the PLC from RUN to STOP, the data can be maintained.
(2) power outage data register D200 D511 (312 points)
Unless rewritten, otherwise the data will not be lost. Deny power or not, PLC running or not, its contents will not be changed. Two PLC for point-to-point communication, D490 D509 is used as a communication operation.
(3) a special data register D8000 D8255 (256 points)
These data register for monitoring various components PLC operation purposes and its contents in the power is switched on (ON), writes an initialization value (all cleared, and arranged by the system ROM write the initial value).
(4) is file register D1000 D2999 (2000)
Used to store large amounts of data, such as data collection, statistical calculations, multiple set of control parameters and so on. Their number determined by the CPU monitoring software, but can be expanded by the method of expansion memory card. It takes up a store inside the user program memory, with 500 points as a unit, up to 2000 can be set when the parameter is set, use the programmer to write.
PLC operation, using BMOV instruction data file registers can be read in general-purpose data registers, but cannot use command writes data to the file register.

FX series PLC soft component-input relay x and Output relay y

1. enter a relay (x)
Enter relay is specifically designed to receive the input signal in the PLC‘s internal virtual relays. It was done by a PLC works relay function. It is inside the PLC connected to the input terminals, it has an infinite number of normally open and normally closed contacts, these dynamic, fixed broken contact in PLC programming, free to use. This input relay will not program driven, driven only by the input signal.
FX series PLC input relay using an octal number. FX2N series PLC with extensions up to a maximum of 184 point input relay, its number is X0 X267.
2. output relay (Y)
The output relay is designed to result in the PLC signal output interface circuit and output terminals serve virtual relay and control an external load. It is directly connected to the output interface circuit in the PLC, which has a myriad of dynamic contact and breaking contact, these moves and break contacts in PLC programming, free to use. External times there is no direct drive relays, it can only use the program drive.

PLC internal counters (c)

Internal counter for the PLC‘s internal image register (X,Y,M,S) provides the signal count, count pulse for the duration of the ON or OFF, should be greater than the PLC scanning cycle, the response rate is typically less than dozens of cycles per second.
1. 16-bit and counter
16-bit and a counter value for l~32767. Figure 313 shows the work process of adding counters, X10 normally open contact connected in this image, C0 is reset, it corresponds to the storage unit is set to 0, it‘s normally open disconnect, connect normally closed contact, while the counting current value is reset to 0. X11 is used to provide a count of the input signal, when the reset of the counter input circuit, counting input circuits from open to close (that is, count the rising edge of the pulse), the counter‘s current value plus 1. 5 after the pulse, the C0 set value is equal to the current value of 5, which correspond to the contents of the storage unit is set to 1, the normally open contacts connected normally closed contacts disconnect. To count the pulse current value unchanged until the reset input circuit, the current value of the counter is reset to 0. Can also be specified through the data register to set the value of the counter.
With reserve battery of counter/latch function can maintain its state information when the power again after the transmission to resume working immediately when you press the power off State.
2. 32-bit bidirectional counter
C200~C234 32-bit bidirectional counter value is2 147 483 648~+2 147 483 647, plus/minus count set by the special auxiliary relays M8200~M8234, when the corresponding special auxiliary relay ON, count reduction, whereas for plus counts.
32-bit counter value in addition to the set by the constant k, but can also be set by specifying the data register, 32-bit value stored in two data registers connected to the component number. If you specify a D0, the settings stored in the D1 and D0. C200 in Figure 314 set the value to 5, and count, if the current value of the counter by 45, the output contact of the counter ON, current value of 5 o’clock, output contact is still ON. Current value by 54 o’clock, output contact OFF, current value of 4 o’clock, the output contacts remain OFF.
The current value of the counter at the time of maximum of 2 147 483 647 plus 1 will become minimum2 147 483 648, similarly, reduced current value2 147 483 648 1 o’clock, will change to a maximum value of 2 147 483 647, the counter is called a ring counters.
Figure 3 – 14 in the reset entered X13 of often open touch points connected Shi, C200 was reset, its often open touch points disconnect, often closed touch points connected, current value was reset for if using battery reserve/lock save counter, in power interrupted Shi, counter stop count, and keep count current value not variable, power again connected Hou in current value of based Shang continues to count, so battery reserve/lock save counter can cumulative count.

Mitsubishi PLC high-speed counter module FX2N-1HC

PLC ladder diagram programs limited the maximum operating frequency of the counter by the scanning cycle, generally only dozens of Hz. In industrial control, sometimes requires fast PLC counting function, pulse count may come from rotary encoders, mechanical switches or electronic switch. High speed counting modules for dozens of even hundreds kHz Hz pulse count, most of them have one or a few discrete output points, the current value of the counter is equal to or greater than the preset value, you can interrupt program change switch output status in a timely manner. This process has nothing to do with the PLC scanning process can ensure the load is driven.
High speed counting modules of the FX2N FX2N-1HC 1 high speed counter, can be used for single phase/dual phase 50kHz of high speed counter, external input or through a PLC program counter can be reset or start counting process, it can be connected to the encoder. When the phase 1 and phase 2 input is less than 50kHz, bipolar input can be set to 1 time multiplier, twice times and 4 times frequency patterns, frequency 50kHz,25kHz and 12.5kHz, respectively. Count value to a 32-bit signed binary number, or two 16-bit unsigned numbers (O~65 535). Count method for automatic plus/minus counts (1 2input/2phase input) or optional plus/minus counts (1phase, 1 input). Available hardware comparer implementation setting value and the values, consistent output, or using software to realize consistent output (maximum delay 200 µ s). It has two NPN open collector output, rated value is DC5~12V,0.5A. Instantaneous value, compare results and error status can be monitored, 8 I/O point in your program.

FX2N series PLC input/output relay introduction

FX series PLC ladder diagram programming elements names letters and digits, they represent the type of component and the component number, such as Y10,M129. Input relay output relay element, represented by the octal number, octal number only 0~7 the 8 digit symbol, follow the every 8 into 1 operation. For example, octal, X17 and X20 are two adjacent integers. Table 33 shows the FX2N series PLC input/output relay components.

1. Enter a relay (x)
Enter relay is the digital signals of PLC receives external input window. PLC optical Coupler, to read external signals into registers and stored in the input image. Input an external normally open or normally closed contacts, or series-parallel circuit consisting of multiple contact points or electronic sensors (proximity switches). In a ladder diagram, can be used multiple times to enter relay normally open contact and a normally closed contact.
Figure 36 shows a diagram of the PLC control system, X0 Terminal input of the external circuit is switched on, the input image register1 status to which it corresponds, disconnected to a 0 State. Enter the relay status depends only on external input signal status, it is not possible under the control of the user program, and must not appear in a ladder diagram enter the relay‘s coil.
Because PLC is read at the beginning of each scan cycle time of the input signal, the input signal is ON or OFF duration should be greater than the PLC scanning cycle. If this condition is not met, input signal may be lost.
2. output relay (Y)
Output relay is the PLC sends signals to the external load window. Output relay output signal to PLc
To the output module, which then drive the external load. If the coil of ladder diagram in Figure 3-6 Y4 power on, relay output modules corresponding to the hardware relay normally open contact is closed, the external load work. Each hardware module relay output only a pair of constant open contacts, but in a ladder diagram, each output relay normally open and normally closed contacts can be used more than once.

FX2Nc series PLC performance profile (basic unit, extension)

FX2NC has very high performance volume and communication capabilities, can be installed to a PLC in a much smaller space than standard. I/O connectors wiring costs can be reduced, saving connection time. I/O point numbers can be extended to 256, optional real-time clock, can connect up to 4 specific modules. Take advantage of built-in features, can control two axes (including interpolation function) by increasing the spread
Show unit can control multiple axes.
Through communication expansion board or special adapters can achieve a variety of communication and data link, such as the CCLink,Profibus,DeviceNet open network communications, and RS485 communications RS232C, N:N link, parallel link, computer links, and I/O link. FX2NC series FX0N and FX2N extension modules can also be used.

FX series PLC user environments, and data structure

It consists of user data, user components distribution, storage, file storage, user parameters by the user program area.
1. User data structure
User data structure is divided into three main categories:
First class is a bit of data. Second class is character data. Third class for words mixed with bit
2. Logic elements
(1) enter relay (X0 ~ X177) PLC input is received from an external switch signals window. Input of the FX2 relays up to a maximum of 128 points, use the octal numbers, and not program driven.
(2) the output relays (Y0 ~ Y177) output terminal of the PLC is to the output signal of the external load window. FX2 relay output can be up to 128, and the number to octal. Drive must be enforced by the output relay of the external load.
(3) auxiliary relay (m)
General auxiliary relay M0 ~ M499 (500 points)
power maintaining M500 ~ M1023 auxiliary relay (524)
M8000 ~ special auxiliary relays M8255 (256 points)
(4) element (s)
In stepping sequential control system programming status symbol in s is an important software component. It with the latter stepping sequential control instruction of STL in combination. There are four types:
Initial state S0 ~ S9 (10 points) back to zeroS10 ~ S19 (10 points)
The S20, ~ S499 (480) keep the S500 ~ S899 (400 points)
(5) alarm system (s) used as alarm status symbol: S900 ~ S999 (100 points). Part of the condition element can be used as an external fault diagnostic output.
(6) the pointer (P/I)
branch instruction pointer P0 ~ P63 (64 points)
break, using the pointer, I0~ I8 (9 points)
(7) the timer (t) (Word, bit)
Timer actions and components
Inside the PLC, the timer is based on cumulative timing clock pulse, clock pulse 1ms, 10ms, 100ms, the time when the meter reaches the set value, the output contact action.
Timer component, and set values and actions is as follows:
Timer (T0 ~ T245)
T0 ~ 100ms timer T199 (200 points)
Setting value 0.1 ~ 3276.7 seconds
T200 ~ 10ms timer T245 (46 points)
Set value of 0.01 to 327.67 seconds
(B) integrating timer (T246 ~ T255)
II the timing and accuracy of contact

From driving timer coil to contacts action, timing accuracy of contact generally represents available:
(8) counter (c) (Word, bit)
internal signal counter
Internal signal counter when a scan is performed on the internal components (such as x, y, m, s, t, and c), the counter counts the number of signals.
Increased 16 bit counters
There are two types of 16 bit binary counter increases:
General: C0 ~ C99 (100 points)
Power outages remain: C100 ~ C199 (100 points)
Their set values between K1 ~ K32767
32 bit bidirectional counter
Increase/decrease of two 32 bit counters:
Universal counter C200 ~ C219 (20 points)
Keep the counter C220 ~ C234 (15 points)
The set value is2147483648 ~ +2147483647, counting direction determined by the special auxiliary relay M8200 ~ M8234. Special auxiliary relay switch on (set to 1) for reduction count when, otherwise count increases.
II high speed counter
C235 to C255 (21 points) is a high speed counter, but they share the same 6 high speed counter on PLC inputs (X0 ~ X5). Selection of high speed counter is not arbitrary, it depends on the type and speed of the counter you want to enter the Terminal. Counter types is as follows:
1 no start/reset terminals C235 ~ C240
1/start/reset terminals C241 ~ C245
2phase bi-directional C246 ~ C250
2phase A-Bphase C251 ~ C255
Figure 6-16 high speed counter
(9) the data register (d) (Word)
Programmable controller for analog control, position control,
Work requires a lot of data, it registers the storage parameters and data.
General data register D0 ~ D199 (200 points)
If no other data are written, have been written to the data does not change. However, the PLC status by running (RUN) stop (STOP), all data is cleared.
power outage data register D200 ~ D511 (312 points)
As above, unless rewritten, otherwise the data will not be lost. Whether the power is switched on or not, PLC running or not, its content does not change. Two PLC for point-to-point communication, the D490 ~ D509 is used as a communication operation.
a special data register D8000 ~ D8255 (256 points)
The PLC data register for monitoring operation of various components in use. Its content in the power is switched on (ON), writes an initialization value (all cleared, and arranged by the system ROM write initialization values).
file registers D1000 ~ D2999 (2000)
File register is actually a kind of special data registers, used to store large amounts of data, such as data collection, statistical calculations, multiple set of control parameters and so on.
Indexing registers (V/Z) (Word)
Indexing registers in a role similar to the z-80 index registers, IX, and IY, is commonly used to modify the element number of the soft component. V and z are 16 bit data register.