Mitsubishi Electric MELSEC FX3U-485ADP-MB Hardware Manual page 5

3. Power supply/input/output specifications
and examples of external wiring
DESIGN
PRECAUTIONS
• Make sure to have the following safety circuits outside of the
PLC to ensure safe system operation even during external
power supply problems or PLC failure.
Otherwise, malfunctions may cause serious accidents.
1) Most importantly, have the following: an emergency stop
circuit, a protection circuit, an interlock circuit for opposite
movements (such as normal vs. reverse rotation), and an
interlock circuit (to prevent damage to the equipment at the
upper and lower positioning limits).
2) Note that when the PLC CPU detects an error, such as a
watchdog timer error, during self-diagnosis, all outputs are
turned off. Also, when an error that cannot be detected by
the PLC CPU occurs in an input/output control block,
output control may be disabled.
External circuits and mechanisms should be designed to
ensure safe machinery operation in such a case.
3) Note that when an error occurs in a relay, triac or transistor
output device, the output could be held either on or off.
For output signals that may lead to serious accidents,
external circuits and mechanisms should be designed to
ensure safe machinery operation in such a case.
DESIGN
PRECAUTIONS
• Do not bundle the control line together with or lay it close to the
main circuit or power line. As a guideline, lay the control line at
least 100mm (3.94") or more away from the main circuit or
power line.
Noise may cause malfunctions.
• Install module so that excessive force will not be applied to
peripheral device connectors, power connectors or input/output
connectors.
Failure to do so may result in wire damage/breakage or PLC
failure.
Notes
• Simultaneously turn on and off the power supplies of the main
unit and extension devices.
• Even if the power supply causes an instantaneous power failure
for less than 5ms, the PLC can continue to operate.
• If a long-time power failure or an abnormal voltage drop occurs,
the PLC stops, and output is turned off. When the power supply
is restored, it will automatically restart (when the RUN input is
on).
WIRING
PRECAUTIONS
• Make sure to cut off all phases of the power supply externally
before attempting installation or wiring work.
Failure to do so may cause electric shock or damage to the
product.
WIRING
PRECAUTIONS
• Connect the DC power supply wiring to the dedicated terminals
specified in this manual. If an AC power supply is connected to
a DC input/output terminal or DC power supply terminal, the
PLC will burn out.
WIRING
PRECAUTIONS
• Do not wire vacant terminals externally.
Doing so may damage the product.
• Perform class D grounding (grounding resistance: 100Ω or
less) to the grounding terminal on the main unit.
Do not use common grounding with heavy electrical systems
(refer to section 3.2).
• When drilling screw holes or wiring, make sure cutting or wire
debris does not enter the ventilation slits.
Failure to do so may cause fire, equipment failures or
malfunctions.
Notes
• Input/output wiring 50 to 100m (164'1" to 328'1") long will cause
almost no problems of noise, but, generally, the wiring length
should be less than 20m (65'7") to ensure the safety.
• Extension cables are easily affected by noise. Lay the cables at
a distance of at least 30 to 50mm (1.19" to 1.97") away from the
PLC output and other power lines.
3.1 Power supply specifications and example of
external wiring
→ For more details, refer to FX
Series User's Manual
3UC
- Hardware Edition.
3.1.1 Power supply specifications
The specifications for the power supply of the main unit are shown in
the following table.
Item Specification
24V DC +20% -15%*
Supply voltage
Ripple Voltage (p-p)5% or
less
Operation can be continued
Allowable instantaneous power upon occurrence of an
failure time instantaneous power failure
for 5ms or less.
Power fuse 125V 3.15A
Rush current 30A max.0.5ms/24V DC
FX -16MT/D,DSS 6W
3UC
FX -32MT/D,DSS 8W
3UC
Power
consumption *1
FX -64MT/D,DSS 11W
3UC
FX -96MT/D,DSS 14W
3UC
FX -16MT/D,DSS 600mA
3UC
5V DC
FX -32MT/D,DSS 560mA
3UC
built-in
power
FX -64MT/D,DSS 480mA
3UC
supply *2
FX -96MT/D,DSS 400mA
3UC
*1 Input/output extension blocks and special function units/blocks
a r e n o t c o n t a in e d i n p o we r c o n s u mp t i on . Fo r p o we r
consumption of the FX input/output extension blocks, refer
2NC
to the following table.
→Refer to the FX
Series User's Manual - Hardware Edition.
3UC
→For the power consumed by the special function units/blocks,
refer to the appropriate manuals.
Model names Power consumption
FX -16EX-T(-DS) 2.2W
2NC
FX -16EX(-DS) 2.2W
2NC
FX -32EX(-DS) 4.2W
2NC
FX -16EYR-T(-DS) 2.2W
2NC
FX -16EYT(-DSS) 0.35W
2NC
FX -32EYT(-DSS) 0.7W
2NC
*2 Cannot be used to supply power to an external destination.
This power is supplied to input/output extension blocks, special
extension blocks and special adapters only.
3.1.2 Example of external wiring (power type)
Supply 24V DC power to the main unit and FX
the dedicated connector.
→For the details of wiring work, refer to Section 2.4
→For the power supply wiring of the FX
blocks, refer to the Subsection 3.3.3
Use a 24V DC +20% -15% DC power supply whose ripple (p-p) is
within 5%. The allowable range of the 24V DC power supply may be
narrower when special function blocks/units are connected.
→For more details, refer to the FX
3UC
Circuit protector
Power on Emer-
1
PL
PLC
MC
Fuse
*
MC
*Class D grounding
Refer to section 3.2
for details.
Power supply for loads connected
to PLC output terminals
3.2 Grounding
Ground the PLC as stated below.
• Perform class D grounding. (Grounding resistance: 100 Ω or less)
• Ground the PLC independently if possible.
If it cannot be grounded independently, ground it jointly as shown
below.
Other Other
PLC PLC
equipment equipment
Independent grounding Shared grounding
(Best condition) (Good condition)
• Position the grounding point as close to the PLC as possible to
decrease the length of the ground wire.
3.3 Input specifications and external wiring
→For more details, refer to the FX
3.3.1 Input specifications
Item
FX
FX
FX
Number of input
FX
points
FX
FX
- EX(-T) using
2NC
FX
FX
Input connecting
FX
input extension
2NC
type
FX
FX
FX
FX
Input form
Series User's Manual -
FX
Hardware Edition
FX
FX
24V DC
Input signal 24V DC +20% -15%
voltage Ripple Voltage (p-p)5% or less
X000 to X005
X006, X007
Input
impedance
gency X010 or more
stop Input extension blocks
MC
X000 to X005
X006, X007
Input signal
current
X010 or more
Input extension blocks
X000 to X005
MC
X006, X007
ON input
sensitivity current
X010 or more
Input extension blocks
Input OFF current 1.5mA or less
Input response
Approx. 10ms
time
FX
FX
FX
Input signal form
FX
Other
PLC
equipment
FX
FX
Common grounding
(Not allowed)
Circuit insulation Photocoupler insulation
Series User's Manual -
3UC
Hardware Edition
Input specification(24V DC)
-16MT/D(SS) 8 points
3UC
-32MT/D(SS) 16 points
3UC
-64MT/D(SS) 32 points
3UC
-96MT/D(SS) 48 points
3UC
-16EX(-DS) 16 points
2NC
-32EX(-DS) 32 points
2NC
-16EX-T(-DS) 16 points
2NC
- MT/D(SS)
3UC
connector
- EX(-DS)
2NC
-16EX-T(-DS) Terminal block
2NC
- MT/D
3UC
- EX Sink
2NC
-16EX-T
2NC
- MT/DSS
3UC
- EX-DS Sink/Source
2NC
-16EX-T-DS
2NC
3.9kΩ
3.3kΩ
*1
4.3kΩ
6mA/24V DC
7mA/24V DC
*1
5mA/24V DC
3.5mA or more
4.5mA or more
*1
3.5mA or more
*2
No-voltage contact
- MT/D
3UC
input
- EX
2NC
NPN open collector
-16EX-T
2NC
transistor
• Sink input :
No-voltage contact
input
NPN open collector
- MT/DSS
3UC
transistor
- EX-DS
2NC
• Source input :
-16EX-T-DS
2NC
No-voltage contact
input
PNP open collector
transistor