Mitsubishi FX3G-14MR/ES, Руководство по установке

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FX3G INSTALLATION MANUAL
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self-retaining circuit. (The operation to forcibly turn on timers is effective only when
the timers are driven by the program.)
- The results of forcible ON/OFF operation performed while the PLC in the
stopped state or performed for devices not used in the program are retained.
However, the results of the operation performed for the input relays (X) are not
retained because the relays refresh input even while the PLC is in the stopped
state. (They are updated according to the input terminal conditions.)
2. Since the current values may be changed according to MOV instruction in the
program and the operation results, the most recently obtained values are retained.
3. Only display modules can change the current value by the extension file register
test function.
4. The current values of the file registers stored in the program memory cannot be
monitored or tested on the display module.
5. Change of timer and counter settings. The settings of the timers (T) and counters
(C) can be changed only when the timers are driven by the program.
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PROGRAM MODIFICATION FUNCTION
The sequence program can be transferred while the PLC is running or
in the stopped state as shown below.
X: Effective – : Ineffective
Item
In Running
Status
In Stopped
Status
Batch Writing of File Registers (D) and Extension
File Registers (ER)
–
X
Writing of
Program to
PLC
Partial Modification of Program X X
Modification of whole Program
(Batch Writing)
–
X
Writing of Parameters to PLC
–
X
Writing of Comments to PLC
–
X
1. Since the writing function is used during running, the programming tool must
support the write during RUN function, such as GX Works2 o r GX Developer.
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BUILT-IN VARIABLE ANALOG POTENTIOMETER FUNCTION
The main unit has two built-in variable analog potentiometers (shown
in the figure below). The current value increases from 0 to 255 when a
variable analog potentiometer is turned clockwise.
The current value of each variable analog potentiometer is stored in
special data registers shown below.
Volume Data Register to Store Current Value
VR1 : variable analog potentiometer1 D8030 (Integer from 0 to 255)
VR2 : variable analog potentiometer2 D8031 (Integer from 0 to 255)
Use example 1 of variable analog potentiometer
The current value of VR1 is used as the set value of a timer.
Use example 2 of variable analog potentiometer
The current value of VR2 multiplied by “10” is used as the set value of
a timer.
7. MAINTENANCE
This PLC does not incorporate consumable parts that are factors in the
reduction of service life. However, the output relays (points of contact)
and batteries (option) have a limited life expectancy.
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PERIODIC INSPECTION - BATTERY LIFE, ETC.
1. BATTERY
Model FX3U-32BL battery: Standard life: 5 years (at ambient
temperature of 25°C (77°F))
2. OTHER DEVICES
When inspecting the battery, check the following points.
„ „
Check that the temperature in the panel is not abnormally
increased by other heat generating bodies or direct sunlight.
„ „
Check that dust or conductive dust has not entered the panel.
„ „
Check for loosening of wiring and other abnormalities.
3. BATTERY REPLACEMENT
When the battery voltage drops while the PLC power is on, the “ALM”
LED on the panel is lit in red, and M8005 and M8006 (latch) are turned
on. The memory can be retained for about one month after the lamps
turn on. However, the operators may not immediately find the lamps to
be on. Prepare a new battery promptly, and replace the battery with the
new one.
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MAINTENANCE – PRODUCT LIFE OF RELAY CONTACTS
The product life of relay contacts varies considerably depending on the
load type used. Take care that loads generating reverse electromotive
force or rush current may cause poor contact or deposition of contacts
which may lead to considerable reduction of the contact product life.
INDUCTIVE LOAD
Inductive loads generate large reverse electromotive force between
contacts at shutdown, which may cause arcing. At a fixed current
consumption, as the power factor (phase between current and voltage)
gets smaller, the arc energy gets larger.
The standard life of contacts used for Inductive loads, such as
contactors and solenoid valves, is 500,000 operations at 20VA. The
following table shows the approximate life of a relay based on the
results of an operation life test.
Load Capacity Contact Life
20VA
0.2A/100VAC
3,000,000 times
0.1A/200VAC
35VA
0.35A/100VAC
1,000,000 times
0.17A/200VAC
80VA
0.8A/100VAC
200,000 times
0.4A/200VAC
The product life of relay contacts becomes considerably shorter than
the above conditions when the rush overcurrent is shut down.
Some types of inductive loads generate rush current 5 to 15 times
Enlarged view
D0 The current value of VR2 multiplied by "10" is used as the
set value of the timer T1.
The setting range in this example using T1 (100ms timer)
is from 0 to 255 sec.
MUL
M8000
T1
D8031 K10 D0(D1)
The value of D8031 is multiplied by "10", and stored in
D0(D1).
D8030
T0
The current value of VR1 is used as the set value of the timer T0.
The setting range in this example using T0 (100ms timer) is from 0 to
25.5 sec.