Mitsubishi FX3UC SERIES User Manual page 190

FX Series Programmable Controllers
3UC
User's Manual - Hardware Edition
5. Output current
The max current per output point is 0.3A. However, to restrict temperature rise, the max current per one
output from four points should be 0.8A (average per point is 0.2A).
When a load with high rush current is turned on and off frequently, the root-mean-square current should be
0.2A or less.
<Example>
× 0.02 + 0.4
2
4
0.02 + 0.7 + 10
6. Open circuit leakage current
A C-R absorber is connected for turn-off in parallel with the triac output terminal of this type of PLC.
Therefore, when the circuit opens, a leakage current will be 1mA at 100V AC and 2mA at 200V AC.
Since the triac output type devices leak current when the circuits are open, small-size relays and micro
current loads having low rated operating current may keep operating even when the triac output is turned off.
Therefore, use a load of 0.4VA or more at 100V AC or 1.6VA or more at 200V AC. If the load is less than this
value, connect a surge absorber as stated below in parallel with the load.
6.4.3 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. Micro current load
The PLC's internal Triac output circuit is equipped with a turn-
off C-R absorber. When connecting a very low current load of
"0.4VA/100V AC or less, or 1.6VA/200V AC or less", please
connect a surge absorber 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.
Item
Static electricity capacity
Resistance value
Reference
Manufacturer
Okaya Electric Industries Co., Ltd. CR-10201
3. Interlock
For loads such as forward/reverse contactors, etc., where a
hazardous condition
simultaneously, an external interlock should be provided for
interlocking the PLC's internal programs as shown to the
right.
184
4A
× 0.7
2
= 0.2A
0.02
sec
→ For the connection of the surge absorber, refer to Subsection 6.4.3
Standard
Approx. 0.1µF
Approx. 100 to 200Ω
Model name
could result if switched
6 Output Specification and External Wiring
6.4 Triac (SSR) Output [FX2N-16EYS]
0.4A
0.7 10
sec sec
"External wiring precaution".
Fuse
Manufacturer
Rubycon Corporation
ON
PLC output
element
Load
Y 0
COM1
PLC
Micro current load
Surge
absorber
Model name
250MCRA104100M B0325
Inter- Limit of normal
lock rotation
Normal
rotation
Reverse
rotation
Limit of reverse
rotation