Mitsubishi FX2-16E series, User Manual

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454
FX
3U
Series Programmable Controllers
User’s Manual - Hardware Edition
20 FX-16/32E*-*-TB (Terminal Block)
20.7 FX-16EYR-TB
20.7.4 External wiring precautions
1. Protection circuit for load short-circuits
A short-circuit at a load connected to an output terminal
could cause burnout at the output element or the PCB. To
prevent this, a protection fuse should be inserted at the
output.
2. Contact protection circuit for inductive loads
An internal protection circuit for the relays is not provided for the relay output circuit in the terminal block. It is
recommended to use inductive loads with built-in protection circuits. When using loads without built-in
protection circuits, insert an external contact protection circuit, etc. to reduce noise and extend the product
life.
1) DC circuit
Connect a diode (for commutation) parallel to the
load.
The diode (for commutation) must comply with the
following specifications.
2) AC circuit
C o n n e c t t h e s u r g e a b s o r b e r ( c o m b i n e d C R
components such as a surge killer and spark killer,
etc.), parallel to the load.
Select the rated voltage of a surge absorber that is
suitable for the load being used. Refer to the table
below for other specifications.
Reference
3. Interlock
For loads such as forward/reverse contactors, etc., where
a hazardous condition could result if switched ON
simultaneously, an external interlock should be provided
for interlocking the PLC’s internal programs as shown to
the right.
4. In-phase
PLC output contacts (*) should be used in an "in-phase"
manner.
Item Guide
Reverse voltage 5 to 10 times the load voltage
Forward current Load current or more
Item Guide
Static electricity capacity Approx. 0.1
µ
F
Resistance value Approx. 100 to 200
Ω
Manufacturer Model name Manufacturer Model name
Okaya Electric Industries Co., Ltd. CR-10201 Rubycon Corporation 250MCRA104100M B0325
Terminal block
0 to 7
COMn
Load
Fuse
inductive load
PLC output
contact
Diode
(for commutation)
inductive load
Surge
absorber
PLC output
contact
Reverse limit
Interlock
PLC output
contact
PLC output
contact
Forward limit
*
*
*
*
Bad
Good