Mitsubishi M80 series, Connection And Set Up Manual

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M800S/M80 Series Connection and Setup Manual
4 General Specifications
104 IB-1501269-F
Precautions
(1) Influence on the relay life by a connected load
An actual relay life can be substantially shortened depending on the type of a connected load and the
characteristics of its inrush current.
The inrush current generated by a connected load can lead to contact welding of the module. To prevent
shortening of the relay life and contact welding, take the following measures:
・
Considering the possibility of a high inrush current, select a load so that the inrush current generated by
the connected load falls within the range of the rated current of the module.
・
Connect a relay capable of withstanding the inrush current, outside the module.
The following table lists the relations between typical loads and each inrush current.
Select a load so that the inrush current, i, and rated current, io, fall within the range of the rated switching
current described in the module specifications.
n some loads, the inrush current flows for a long time.
(Note 1) A typical discharge lamp circuit is configured with a combination of discharge tubes,
transformers, choke coils, capacitors and others. Because of this, be especially careful of the
case of a high power factor and a low power supply impedance, where the inrush current
flowing into the output module can be 20 to 40 times as high as the rated current.
(Note 2) When the wiring is long, be careful with the cable capacity as well.
Load type Waveform
Inrush
current i/
rated current
io
Waveform
Inrush
current i/
rated current
io
Inductive
load Approx. 10 to
20 times Approx. 3 to
10 times
Lamp load
Approx. 3 to
10 times
Approx. 3
times (Note
1)
Approx. 5 to
10 times
- -
Capacitive
load Approx. 20 to
40 times
- -
i io
Load of a solenoid
0.07 to 0.1 seconds
i: Inrush current
io: Rated current
i io
0.017 to 0.033 seconds
(1 to 2 cycles)
Load of an electromagnetic contactor
i: Inrush current
io: Rated current
io i
Load of an incandescent bulb
Approx. 0.33 seconds
i: Inrush current
io: Rated current
i io
Load of a mercury lamp
180 to 300 seconds
(3 to 5 minutes)
i: Inrush current
io: Rated current
io i
Load of a fluorescent
Within 10 seconds
i: Inrush current
io: Rated current
io
i
Capacitive load (Note 2)
0.008 to 0.33 seconds
(0.5 to 2 cycles)
i: Inrush current
io: Rated current